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Memory AnchorsCivil Service Exam (Professional) · Numerical Ability

Civil Service Exam (Professional) Numerical Ability — Word Problems — Speed/Distance/Age, Discount & InterestMemory Anchors

Memory aids for Word Problems — Speed/Distance/Age, Discount & Interest in the Civil Service Exam (Professional): mnemonics, analogies and recall chains for the facts that are easy to mix up.

Super Tutor's review for Civil Service Exam (Subprofessional) uses these same chapters, so they live here in the Civil Service Exam (Professional) section.

Word Problems — Speed/Distance/Age, Discount & Interest - Memory Anchors

Memory techniques transform abstract mathematical concepts into unforgettable images and stories. These creative memory aids turn formulas into vivid stories, complex problems into familiar analogies, and boring numbers into exciting adventures. Your brain naturally remembers stories, emotions, and visual images better than abstract concepts—so let's make every formula and problem-solving step stick in your mind forever!

Memory anchors

Speed = Distance ÷ Time formula

Speed/Distance/Timeeasyacronym

Memory aid

Super Dog Travels - SDT triangle where Speed is at the top, Distance and Time at the bottom. Cover what you want to find!

Why it works

Visual triangles create spatial memory, and the silly 'Super Dog Travels' phrase makes it emotionally memorable

Example usage

When asked 'A jeepney travels 150km in 3 hours, find its speed' - think Super Dog Travels, cover S in triangle, get D÷T = 150÷3 = 50 kph

Recall trigger

Picture a superhero dog flying through the air when you see speed problems

Simple Interest formula I = PRT

Simple Interestmediummicro story

Memory aid

A pirate named Captain PRT buried treasure. To find his Interest (I), he needed his Principal (P) gold coins, the Rate (R) of growth per year, and Time (T) buried underground. I = P × R × T

Why it works

Pirates and treasure create strong emotional connections, making the abstract formula concrete and memorable

Example usage

For 'Find interest on P10,000 at 5% for 2 years' - Captain PRT: I = 10,000 × 0.05 × 2 = P1,000

Recall trigger

Think of a pirate counting treasure when you see interest problems

Discount formula: Discount = List Price - Selling Price

Discounteasyvisual association

Memory aid

Imagine a price tag with two numbers: the BIG original price and the SMALLER sale price. The discount is the chunk that got 'eaten away' between them - like a pac-man chomping the difference!

Why it works

Visual imagery of Pac-Man eating the price difference creates a strong mental picture that's hard to forget

Example usage

T-shirt listed at P500, sold at P400. Pac-man ate P500 - P400 = P100 discount

Recall trigger

Picture Pac-Man eating money when you see discount problems

Age problems - setting up present, past, and future ages

Age Problemshardanalogy

Memory aid

Age problems are like time machines! Create a table with three columns: Past (subtract years), Present (now), Future (add years). Each person is a time traveler with their own journey.

Why it works

Time travel is exciting and familiar from movies, making abstract age relationships concrete and visual

Example usage

Maria is 3 times older than Juan. In 5 years, she'll be twice as old. Set up: Present (M=3J), Future (M+5=2(J+5))

Recall trigger

Think 'Back to the Future' when solving age problems

Compound Interest vs Simple Interest difference

Compound Interestmediumanalogy

Memory aid

Simple Interest is like a lazy employee - earns the same amount each year. Compound Interest is like an ambitious entrepreneur - earns money on the money it already earned, growing exponentially like a snowball rolling downhill!

Why it works

Contrasting personalities (lazy vs ambitious) and familiar images (snowball) make the concepts distinct and memorable

Example usage

P1,000 at 10%: Simple stays flat (100+100+100), Compound grows (100+110+121)

Recall trigger

Picture a lazy person vs a snowball when comparing interest types

Converting km/hr to m/s

Speed Conversionmediummnemonic

Memory aid

King Henry's Magic: Multiply by 5, Divide by 18. Or remember 'Keep Happy, Make Sure' - K(m)/H(r) to M(eters)/S(econds) = × 5/18

Why it works

Rhyming phrases and royal imagery create memorable patterns for the conversion factor

Example usage

Convert 72 km/hr: 72 × 5/18 = 20 m/s (King Henry's Magic!)

Recall trigger

Think of King Henry when converting speed units

Average Speed formula

Average Speedmediummicro story

Memory aid

Meet Average Joe - he never rushes or slows down. To find his constant speed on any trip, he adds ALL the distances he traveled and divides by ALL the time it took. Average Speed = Total Distance ÷ Total Time

Why it works

Personifying average speed as 'Average Joe' makes the concept relatable and the formula logical

Example usage

Trip 1: 60km in 1hr, Trip 2: 90km in 2hrs. Average Joe: (60+90)÷(1+2) = 50 kph

Recall trigger

Think of a steady, consistent person named Average Joe

Discount Percentage formula

Discount Percentagemediumvisual association

Memory aid

Imagine a pizza cut into 100 slices (100%). The discount percentage is how many slices you DON'T have to pay for. Discount % = (Original Price - Sale Price) ÷ Original Price × 100

Why it works

Pizza slices make percentages visual and concrete - everyone understands pizza portions!

Example usage

Shoes: P2000 → P1600. Missing pizza slices: (2000-1600)÷2000 × 100 = 20%

Recall trigger

Picture pizza slices when calculating discount percentages

Future Value in Compound Interest F = P(1+r)^t

Compound Interesthardmicro story

Memory aid

Future Fairy grants wishes! She takes your Present money (P), adds the rate (r) to make it grow, then waves her magic wand (1+r) and multiplies it by itself for each year (^t). F = P(1+r)^t

Why it works

Fairy magic explains the mysterious power of exponential growth in a memorable way

Example usage

P10,000 at 5% for 3 years: Future Fairy says F = 10,000(1.05)³ = P11,576.25

Recall trigger

Think of a magical fairy when calculating compound interest

Time conversion in interest problems

Time Conversioneasyrhyme

Memory aid

Months to years, never fear! Divide by twelve, the answer's here! Days to years, don't you cry! Divide by three-sixty-five!

Why it works

Rhymes create rhythm and melody that stick in memory better than plain facts

Example usage

9 months = 9÷12 = 0.75 years, 180 days = 180÷365 = 0.49 years

Recall trigger

Sing the rhyme when you need to convert time units

Setting up age problem equations

Age Problem Strategyhardmethod of loci

Memory aid

Walk through your house: Front door = Present ages (let x be younger person), Living room = Past relationships (subtract years), Kitchen = Future relationships (add years), Bedroom = Write equations and solve

Why it works

Method of loci uses familiar spatial memory to organize complex problem-solving steps

Example usage

Father 4x older than son. In 20 years, only 2x older. House tour: Door(F=4S), Kitchen(F+20=2(S+20)), solve!

Recall trigger

Mentally walk through your house when solving age problems

Types of discount (Trade, Quantity, Promotional)

Types of Discounteasyacronym

Memory aid

TQP - 'Top Quality Products' = Trade (business to business), Quantity (bulk buying), Promotional (marketing/clearance)

Why it works

The phrase 'Top Quality Products' is positive and business-related, making it easy to remember all three types

Example usage

Question asks about discount types - recall TQP: Trade (distributor to retailer), Quantity (bulk discounts), Promotional (sales/clearance)

Recall trigger

Think 'Top Quality Products' when asked about discount types

Distance problems with multiple speeds

Complex Distance Problemshardvisual association

Memory aid

Picture a race track with different lanes - each lane has different speeds but the same distance. Make a table like a scoreboard: Distance | Speed | Time for each 'lane' of the journey

Why it works

Race tracks are visually familiar, and scoreboards naturally organize information in tables

Example usage

Car travels 200km at 50kph, returns same route at 100kph. Scoreboard: Lane 1 (200|50|4), Lane 2 (200|100|2)

Recall trigger

Visualize a race track scoreboard when dealing with complex distance problems

Principal calculation P = I÷(RT)

Principal Calculationmediumanalogy

Memory aid

Principal is like the seed that grows into the Interest fruit. To find the original seed size, you take the fruit (Interest) and divide by how much it grew (Rate × Time). Bigger growth factors mean smaller original seed needed!

Why it works

Seeds growing into fruit is a natural, intuitive process that explains inverse relationships clearly

Example usage

Interest earned P2,400 at 8% for 3 years. Seed size: P = 2,400÷(0.08×3) = P10,000

Recall trigger

Think of seeds growing into fruit when finding principal

Maturity Value calculation M = P + I

Maturity Valueeasyvisual association

Memory aid

Picture a piggy bank growing fat! The Maturity Value is the final fat piggy (M) = Original skinny piggy (P) + All the extra weight it gained (I). Simple addition!

Why it works

Piggy banks are associated with savings, and the visual of growth makes addition logical

Example usage

Invested P50,000, earned P7,500 interest. Fat piggy: M = 50,000 + 7,500 = P57,500

Recall trigger

Picture a piggy bank getting fat when calculating maturity value

Rate calculation R = I÷(PT)

Rate Calculationmediummicro story

Memory aid

Rate Detective investigates: 'How fast did this money grow?' He takes the Interest evidence (I) and divides by the Principal suspect (P) and Time witness (T) to find the growth Rate. R = I÷(P×T)

Why it works

Detective stories create narrative structure, making abstract division meaningful and memorable

Example usage

P20,000 earned P3,000 in 2 years. Detective work: R = 3,000÷(20,000×2) = 0.075 = 7.5%

Recall trigger

Channel your inner detective when finding interest rates

Selling Price calculation after discount

Selling Price Calculationmediumchunking

Memory aid

Think '100 minus discount, then multiply': SP = List Price × (100% - Discount%). Break it into chunks: Step 1: 100 - discount%, Step 2: Convert to decimal, Step 3: Multiply by list price

Why it works

Chunking breaks complex calculations into manageable steps, reducing cognitive load

Example usage

P800 shirt, 25% off. Chunks: 100-25=75%, 75%=0.75, SP = 800×0.75 = P600

Recall trigger

Count '100 minus, then multiply' on your fingers

Age relationship patterns

Age Relationshipshardvisual association

Memory aid

Draw age problems like a family tree that travels through time! Present ages at the trunk, past ages on the left branches (subtract), future ages on right branches (add). Relationships stay proportional as the tree grows!

Why it works

Family trees are familiar visual structures, and the time-travel aspect makes age changes logical

Example usage

Mom 3x older than daughter now, will be 2x older in 10 years. Tree shows: Now(3x|x), Future(3x+10|x+10), equation: 3x+10=2(x+10)

Recall trigger

Sketch a time-traveling family tree for age problems

Word problem identification strategy

Problem-Solving Strategymediumacronym

Memory aid

SWIFT strategy: S-Scan for keywords (speed, discount, age, interest), W-What is being asked?, I-Information given, F-Formula needed, T-Time to calculate! Like a SWIFT response team!

Why it works

SWIFT suggests speed and efficiency, and the military/emergency response analogy makes problem-solving feel organized and confident

Example usage

Problem mentions 'annual rate' and 'how much earned' - SWIFT scan identifies interest problem, formula I=PRT needed

Recall trigger

Deploy SWIFT team tactics when facing any word problem

Common word problem mistake prevention

Error Preventionmediumvisual association

Memory aid

Picture a red STOP sign with common traps: Units not matching (km/hr vs m/s), Time not converted (months to years), Forgetting to add principal to interest, Using wrong formula. The STOP sign prevents crashes!

Why it works

STOP signs are universal warning symbols, creating strong associations with danger/mistakes to avoid

Example usage

About to submit interest calculation - STOP sign reminds to check: Did I convert 6 months to 0.5 years? Did I add principal to get maturity value?

Recall trigger

Visualize a red STOP sign before submitting answers

Revision game

I'm a triangle that helps you travel, with Speed on top and Distance-Time below. What am I?

Answer

SDT Triangle

Memory link

Super Dog Travels memory anchor (A1)

I'm a pirate who counts treasure using P times R times T. Who am I?

Answer

Captain PRT (Simple Interest)

Memory link

Pirate treasure story (A2)

I eat the difference between two prices - the big one and the smaller sale price. What am I?

Answer

Pac-Man Discount

Memory link

Pac-Man eating price difference (A3)

I'm like a time machine with three columns: subtract for past, now for present, add for future. What am I?

Answer

Age Problem Table

Memory link

Time machine analogy (A4)

I'm lazy and earn the same each year, unlike my ambitious snowball friend. What am I?

Answer

Simple Interest

Memory link

Lazy employee vs snowball analogy (A5)

I grant wishes by taking Present money, adding rate, then raising to the power of time. Who am I?

Answer

Future Fairy (Compound Interest)

Memory link

Future Fairy magic story (A9)

I'm a SWIFT team that Scans, asks What, lists Information, finds Formula, then calculates Time. What am I?

Answer

SWIFT Problem-Solving Strategy

Memory link

SWIFT strategy acronym (A19)

I'm a red sign that prevents crashes by warning about units, conversions, and formula mistakes. What am I?

Answer

STOP Sign Error Prevention

Memory link

Red STOP sign visualization (A20)

Formula mnemonics

Speed = Distance ÷ Time

Mnemonic

Super Dog Travels - SDT triangle, cover what you want to find

When to use

Any problem asking for speed, distance, or time in motion

What each part means

Speed (how fast), Distance (how far), Time (how long)

Simple Interest: I = PRT

Mnemonic

I Prefer Reading Tonight - Interest equals Principal × Rate × Time

When to use

When interest is calculated only on the original principal amount

What each part means

I (interest earned/paid), P (principal/original amount), R (rate as decimal), T (time in years)

Compound Interest: F = P(1+r)^t

Mnemonic

Future Perfect - Present grows by (1 plus rate) powered by time

When to use

When interest earns interest (compounds)

What each part means

F (future value), P (present value), r (rate as decimal), t (time periods)

Discount = List Price - Selling Price

Mnemonic

Don't Lose Sales Profits - Discount equals List minus Selling Price

When to use

When finding the peso amount of discount given

What each part means

Discount (amount saved), List Price (original price), Selling Price (final price paid)

Average Speed = Total Distance ÷ Total Time

Mnemonic

All Students Take Tests - Average Speed equals Total Distance over Total Time

When to use

When finding constant speed for trips with different speeds

What each part means

Average Speed (constant speed equivalent), Total Distance (sum of all distances), Total Time (sum of all times)

Quick recall chains

Steps to Solve Speed Problems

Recall test

What are the 5 steps to solve any speed problem?

Memory chain

I Will Surely Calculate Correctly - like a racing driver checking everything before the race

Items to remember

  • Identify what's missing
  • Write the formula
  • Substitute known values
  • Calculate the answer
  • Check units

Age Problem Setup Sequence

Recall test

What 5 steps help organize age problems?

Memory chain

Detective Creates Tables, Writes Reports, Solves Cases - like a detective investigating through time

Items to remember

  • Define variables
  • Create time table
  • Write present relationship
  • Write future/past relationship
  • Solve equations

Interest Problem Types

Recall test

Name the 6 key elements in interest problems

Memory chain

Smart Children Practice Reading Time Management - all the components of interest problems

Items to remember

  • Simple Interest
  • Compound Interest
  • Principal
  • Rate
  • Time
  • Maturity Value

Discount Problem Elements

Recall test

What are the 4 main elements in discount problems?

Memory chain

Lazy Dogs Don't Sell - the four key prices/rates in discount problems

Items to remember

  • List Price
  • Discount Amount
  • Discount Rate
  • Selling Price

Unit Conversion Factors

Recall test

What are the 5 most important conversion factors for word problems?

Memory chain

King Henry's Magic Numbers: 1000, 60, 12, and the magic fractions 5/18 and 18/5

Items to remember

  • 1 km = 1000 m
  • 1 hour = 60 minutes
  • 1 year = 12 months
  • km/hr to m/s: ×5/18
  • m/s to km/hr: ×18/5

Diagrams

Word Problems Master Mind Map

Complete concept map showing all major topics and their relationships in word problems

Word Problem Solving Strategy Flowchart

Step-by-step decision tree for approaching any word problem systematically

Age Problem Time Analysis

Shows the time flow and relationship dependencies in age word problems

Common Word Problem Types Distribution

Shows the relative frequency of different word problem types in Philippine entrance exams

Word Problems — Speed/Distance/Age, Discount & Interest is chapter 6 of 9 in the Numerical Ability part of Super Tutor's Civil Service Exam (Professional) review. The Career Service Examination — Professional Level is given by Civil Service Commission (CSC); its dates, format and passing rules are on the Civil Service Exam (Professional) page. See the Civil Service Exam (Professional) guide.

Study Word Problems — Speed/Distance/Age, Discount & Interest in the Super Tutor app

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