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Exam Answer TemplatesCivil Service Exam (Professional) · Numerical Ability

Civil Service Exam (Professional) Numerical Ability — Fractions — Operations, Conversion & ComparisonExam Answer Templates

Step-by-step answer templates for Fractions — Operations, Conversion & Comparison, from the Numerical Ability part of Super Tutor's Civil Service Exam (Professional) review.

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

Fractions — Operations, Conversion & Comparison - Exam Answer Templates

Mastering fraction problems in exams requires not just mathematical accuracy but also clear, structured presentation of solutions. In Philippine entrance exams like UPCAT, CSE, and NMAT, partial credit is awarded based on proper methodology, clear steps, and correct final answers. These templates show you exactly how to structure your responses for maximum marks across different question types.

Answer templates

Convert 3¾ to an improper fraction.

Fraction Conversioneasyvery short answer1 mark

Examiner tip

Even for 1-mark questions, show the multiplication and addition steps clearly

Model answer

3¾ = (3 × 4 + 3)/4 = 15/4

Answer structure

  • Show the conversion formula and calculate [1 mark]

Scoring breakdown

1 mark

Criteria

Correct conversion using the formula (whole × denominator + numerator)/denominator

Common mark deductions

  • Not showing the multiplication step
  • Incorrect arithmetic
  • Not simplifying when needed

Key phrases to include

  • multiply
  • add
  • improper fraction

Add: 2/3 + 1/4

Addition of Fractionseasyshort answer2 marks

Examiner tip

Always state the LCD clearly - this is a common marking point

Model answer

Step 1: Find LCD of 3 and 4 = 12
Step 2: 2/3 + 1/4 = 8/12 + 3/12 = 11/12

Answer structure

  • Find the LCD [1 mark]
  • Convert fractions and add [1 mark]

Scoring breakdown

1 mark

Criteria

Correctly identifying LCD as 12

1 mark

Criteria

Proper conversion and addition to get 11/12

Common mark deductions

  • Wrong LCD calculation
  • Conversion errors
  • Not adding numerators correctly

Key phrases to include

  • LCD
  • convert
  • add numerators

Arrange in ascending order: 3/5, 2/3, 7/10

Comparing Fractionsmediumshort answer3 marks

Examiner tip

Show each conversion step separately for clarity and partial marks

Model answer

Step 1: Find LCD of 5, 3, and 10 = 30
Step 2: Convert to equivalent fractions:
3/5 = 18/30, 2/3 = 20/30, 7/10 = 21/30
Step 3: Ascending order: 18/30 < 20/30 < 21/30
Therefore: 3/5 < 2/3 < 7/10

Answer structure

  • Find LCD of all denominators [1 mark]
  • Convert all fractions to equivalent fractions [1 mark]
  • Arrange in correct order [1 mark]

Scoring breakdown

1 mark

Criteria

Correctly finding LCD = 30

1 mark

Criteria

Accurate conversion of all three fractions

1 mark

Criteria

Correct final arrangement with proper notation

Common mark deductions

  • Wrong LCD
  • Conversion errors
  • Incorrect final order
  • Missing inequality symbols

Key phrases to include

  • LCD
  • equivalent fractions
  • ascending order

Multiply: 2⅓ × 1¾

Multiplication of Fractionsmediumshort answer3 marks

Examiner tip

Label each conversion clearly to avoid confusion

Model answer

Step 1: Convert to improper fractions:
2⅓ = 7/3, 1¾ = 7/4
Step 2: Multiply: 7/3 × 7/4 = 49/12
Step 3: Convert to mixed number: 49/12 = 4 1/12

Answer structure

  • Convert mixed numbers to improper fractions [1 mark]
  • Multiply the fractions [1 mark]
  • Convert answer back to mixed number [1 mark]

Scoring breakdown

1 mark

Criteria

Correct conversion: 2⅓ = 7/3 and 1¾ = 7/4

1 mark

Criteria

Proper multiplication: 7/3 × 7/4 = 49/12

1 mark

Criteria

Final conversion: 49/12 = 4 1/12

Common mark deductions

  • Conversion errors
  • Multiplication mistakes
  • Not converting final answer

Key phrases to include

  • improper fractions
  • multiply
  • mixed number

Divide: 3/4 ÷ 2/5

Division of Fractionseasyshort answer2 marks

Examiner tip

Always state 'reciprocal method' to show your understanding

Model answer

Step 1: Use reciprocal method: 3/4 ÷ 2/5 = 3/4 × 5/2
Step 2: Multiply: 3/4 × 5/2 = 15/8 = 1⅞

Answer structure

  • Apply reciprocal method [1 mark]
  • Calculate and simplify [1 mark]

Scoring breakdown

1 mark

Criteria

Correctly showing 3/4 ÷ 2/5 = 3/4 × 5/2

1 mark

Criteria

Accurate multiplication and final answer 1⅞

Common mark deductions

  • Not using reciprocal
  • Multiplication errors
  • Not converting to mixed number

Key phrases to include

  • reciprocal
  • multiply
  • invert

Simplify 24/36 to its lowest terms.

Simplifying Fractionseasyshort answer2 marks

Examiner tip

Show the GCF calculation method for full marks

Model answer

Step 1: Find GCF of 24 and 36
24 = 2³ × 3, 36 = 2² × 3²
GCF = 2² × 3 = 12
Step 2: Divide both by GCF: 24/36 = (24÷12)/(36÷12) = 2/3

Answer structure

  • Find the GCF of numerator and denominator [1 mark]
  • Divide both by GCF to get simplified form [1 mark]

Scoring breakdown

1 mark

Criteria

Correctly identifying GCF = 12

1 mark

Criteria

Proper division to get 2/3

Common mark deductions

  • Wrong GCF calculation
  • Division errors
  • Not reaching lowest terms

Key phrases to include

  • GCF
  • lowest terms
  • divide

Convert 0.75 to a fraction in lowest terms.

Decimal to Fraction Conversioneasyshort answer2 marks

Examiner tip

Always check if the fraction can be simplified further

Model answer

Step 1: 0.75 = 75/100
Step 2: Simplify by GCF: GCF of 75 and 100 = 25
75/100 = (75÷25)/(100÷25) = 3/4

Answer structure

  • Convert decimal to fraction with denominator 100 [1 mark]
  • Simplify to lowest terms [1 mark]

Scoring breakdown

1 mark

Criteria

Correctly writing 0.75 = 75/100

1 mark

Criteria

Proper simplification to 3/4

Common mark deductions

  • Wrong initial fraction
  • Incorrect simplification
  • Not finding GCF

Key phrases to include

  • decimal to fraction
  • simplify
  • lowest terms

Maria ate 2/5 of a pizza and her brother ate 1/3 of the same pizza. What fraction of the pizza did they eat altogether?

Word Problems - Additionmediumshort answer3 marks

Examiner tip

Always restate the question in your final answer for word problems

Model answer

Step 1: Add the fractions eaten: 2/5 + 1/3
Step 2: Find LCD of 5 and 3 = 15
Step 3: 2/5 + 1/3 = 6/15 + 5/15 = 11/15
Therefore, they ate 11/15 of the pizza altogether.

Answer structure

  • Identify the operation needed (addition) [1 mark]
  • Find LCD and convert fractions [1 mark]
  • Add fractions and state final answer [1 mark]

Scoring breakdown

1 mark

Criteria

Recognizing this is an addition problem

1 mark

Criteria

Correct LCD = 15 and proper conversion

1 mark

Criteria

Final answer 11/15 with proper conclusion

Common mark deductions

  • Wrong operation
  • LCD errors
  • Missing final statement
  • No units

Key phrases to include

  • add
  • LCD
  • altogether

A recipe calls for 2¼ cups of flour. If you want to make 1½ times the recipe, how much flour do you need?

Word Problems - Multiplicationmediumlong answer5 marks

Examiner tip

Show every step clearly in word problems - each step typically earns marks

Model answer

Step 1: Convert mixed numbers to improper fractions
2¼ = (2×4+1)/4 = 9/4
1½ = (1×2+1)/2 = 3/2

Step 2: Set up multiplication
Flour needed = 2¼ × 1½ = 9/4 × 3/2

Step 3: Multiply the fractions
9/4 × 3/2 = (9×3)/(4×2) = 27/8

Step 4: Convert to mixed number
27 ÷ 8 = 3 remainder 3
27/8 = 3⅜

Therefore, you need 3⅜ cups of flour.

Answer structure

  • Convert mixed numbers to improper fractions [1 mark]
  • Set up the multiplication correctly [1 mark]
  • Perform the multiplication [1 mark]
  • Convert back to mixed number [1 mark]
  • State final answer with units [1 mark]

Scoring breakdown

1 mark

Criteria

Correct conversion: 2¼ = 9/4 and 1½ = 3/2

1 mark

Criteria

Proper setup: 9/4 × 3/2

1 mark

Criteria

Accurate multiplication: 27/8

1 mark

Criteria

Correct conversion: 27/8 = 3⅜

1 mark

Criteria

Complete answer with units and conclusion

Common mark deductions

  • Conversion errors
  • Setup mistakes
  • Arithmetic errors
  • Missing units
  • No final statement

Key phrases to include

  • convert
  • multiply
  • mixed number
  • cups

Compare 7/12 and 5/8 using the symbol <, >, or =.

Comparing Fractionseasyshort answer2 marks

Examiner tip

Always show the converted fractions before stating the comparison

Model answer

Step 1: Find LCD of 12 and 8 = 24
Step 2: Convert: 7/12 = 14/24 and 5/8 = 15/24
Step 3: Since 14/24 < 15/24, therefore 7/12 < 5/8

Answer structure

  • Find LCD and convert fractions [1 mark]
  • Compare and write correct symbol [1 mark]

Scoring breakdown

1 mark

Criteria

Correct LCD = 24 and accurate conversions

1 mark

Criteria

Proper comparison: 7/12 < 5/8

Common mark deductions

  • Wrong LCD
  • Conversion errors
  • Incorrect comparison symbol

Key phrases to include

  • LCD
  • convert
  • compare

Subtract: 5⅔ - 2¾

Subtraction of Mixed Numbersmediumshort answer3 marks

Examiner tip

Double-check your conversion arithmetic - it's a common error point

Model answer

Step 1: Convert to improper fractions:
5⅔ = 17/3, 2¾ = 11/4
Step 2: Find LCD of 3 and 4 = 12
Step 3: 17/3 - 11/4 = 68/12 - 33/12 = 35/12 = 2 11/12

Answer structure

  • Convert mixed numbers to improper fractions [1 mark]
  • Find LCD and subtract [1 mark]
  • Convert final answer to mixed number [1 mark]

Scoring breakdown

1 mark

Criteria

Correct conversions: 5⅔ = 17/3 and 2¾ = 11/4

1 mark

Criteria

Proper LCD = 12 and subtraction: 35/12

1 mark

Criteria

Final conversion: 35/12 = 2 11/12

Common mark deductions

  • Conversion errors
  • Wrong LCD
  • Subtraction mistakes
  • Not converting final answer

Key phrases to include

  • improper fractions
  • LCD
  • subtract
  • mixed number

Which is greater: 3/4 of 80 or 5/6 of 72?

Fraction Operations in Comparisonmediumshort answer3 marks

Examiner tip

Remember that 'of' means multiplication in fraction problems

Model answer

Step 1: Calculate 3/4 of 80
3/4 × 80 = (3 × 80)/4 = 240/4 = 60
Step 2: Calculate 5/6 of 72
5/6 × 72 = (5 × 72)/6 = 360/6 = 60
Step 3: Compare: 60 = 60
Therefore, both values are equal.

Answer structure

  • Calculate first fraction of its number [1 mark]
  • Calculate second fraction of its number [1 mark]
  • Compare and state conclusion [1 mark]

Scoring breakdown

1 mark

Criteria

Correct calculation: 3/4 of 80 = 60

1 mark

Criteria

Correct calculation: 5/6 of 72 = 60

1 mark

Criteria

Proper comparison and conclusion that they are equal

Common mark deductions

  • Arithmetic errors
  • Wrong interpretation of 'of'
  • Missing comparison
  • No conclusion

Key phrases to include

  • of means multiply
  • calculate
  • compare

A tank is 3/5 full of water. If 1/4 of the water is used, what fraction of the tank contains water now?

Complex Word Problemshardlong answer5 marks

Examiner tip

Clearly state what each fraction represents relative to the tank capacity

Model answer

Step 1: Initial water in tank = 3/5 of tank

Step 2: Water used = 1/4 of the water in tank
Water used = 1/4 × 3/5 = 3/20 of tank

Step 3: Water remaining = Initial water - Water used
Water remaining = 3/5 - 3/20

Step 4: Find LCD of 5 and 20 = 20
3/5 = 12/20
Water remaining = 12/20 - 3/20 = 9/20

Therefore, 9/20 of the tank contains water now.

Answer structure

  • Identify initial water fraction [1 mark]
  • Calculate water used as fraction of tank [1 mark]
  • Set up subtraction for remaining water [1 mark]
  • Find LCD and subtract correctly [1 mark]
  • State final answer with proper units [1 mark]

Scoring breakdown

1 mark

Criteria

Recognizing initial water = 3/5 of tank

1 mark

Criteria

Correct calculation: water used = 1/4 × 3/5 = 3/20

1 mark

Criteria

Proper setup: 3/5 - 3/20

1 mark

Criteria

Accurate calculation: 9/20

1 mark

Criteria

Complete final answer with units

Common mark deductions

  • Misunderstanding the problem
  • Calculation errors
  • Wrong operation
  • Missing units
  • Incomplete explanation

Key phrases to include

  • initial
  • used
  • remaining
  • of tank

Express 13/4 as a mixed number.

Improper to Mixed Conversioneasyvery short answer1 mark

Examiner tip

Show the division step briefly even for 1-mark questions

Model answer

13 ÷ 4 = 3 remainder 1, so 13/4 = 3¼

Answer structure

  • Perform division and express as mixed number [1 mark]

Scoring breakdown

1 mark

Criteria

Correct conversion showing 13/4 = 3¼

Common mark deductions

  • Division errors
  • Wrong mixed number format

Key phrases to include

  • divide
  • remainder
  • mixed number

Find the sum: 1/6 + 1/8 + 1/12

Addition of Multiple Fractionsmediumshort answer3 marks

Examiner tip

When adding multiple fractions, organize your work clearly to avoid errors

Model answer

Step 1: Find LCD of 6, 8, and 12
LCM(6,8,12) = 24
Step 2: Convert to equivalent fractions:
1/6 = 4/24, 1/8 = 3/24, 1/12 = 2/24
Step 3: Add: 4/24 + 3/24 + 2/24 = 9/24 = 3/8

Answer structure

  • Find LCD of all three denominators [1 mark]
  • Convert all fractions to equivalent fractions [1 mark]
  • Add and simplify [1 mark]

Scoring breakdown

1 mark

Criteria

Correct LCD = 24

1 mark

Criteria

Accurate conversion of all three fractions

1 mark

Criteria

Proper addition and simplification to 3/8

Common mark deductions

  • Wrong LCD calculation
  • Conversion errors
  • Addition mistakes
  • Not simplifying final answer

Key phrases to include

  • LCD
  • equivalent fractions
  • add
  • simplify

Mark wise strategy

Direct application of formulas or simple conversions with minimal working

1 mark1-2 lines30-60 seconds

Do

  • Show key step clearly
  • Write final answer
  • Use proper notation

Don't

  • Skip showing any work
  • Make careless arithmetic errors
  • Forget to simplify

Two clear steps with intermediate results shown

2 marks3-4 lines1-2 minutes

Do

  • Label each step
  • Show LCD calculations
  • Verify final answer

Don't

  • Combine multiple steps
  • Skip intermediate results
  • Forget units in word problems

Three distinct steps with clear progression and proper explanations

3 marks4-6 lines2-3 minutes

Do

  • Number your steps
  • Show all conversions
  • State final conclusion clearly

Don't

  • Rush through calculations
  • Skip conversion steps
  • Leave answers unsimplified

Comprehensive solution with detailed working, clear logic, and complete explanations

5 marks8-12 lines4-6 minutes

Do

  • Break into logical steps
  • Explain your reasoning
  • Include units throughout
  • Double-check calculations

Don't

  • Jump steps
  • Mix up different methods
  • Forget to answer the actual question
  • Leave working unclear

General answer writing tips

  • Always show your complete working, even for simple calculations - examiners award marks for correct methodology
  • Use proper fraction notation and simplify all final answers to lowest terms
  • Label each step clearly when converting between mixed numbers and improper fractions
  • Include units in word problems and box your final answer for easy identification
  • When comparing fractions, show the LCD calculation process step by step
  • Draw clear diagrams for fraction visualization when appropriate
  • Use the reciprocal method notation clearly in division problems
  • Check your answer by substitution or estimation to avoid careless errors

Diagrams

Fraction Operations Overview

Complete overview of all fraction operations covered in the chapter, showing relationships between different types of problems

Adding Fractions Step-by-Step Process

Decision tree showing the complete process for adding any two fractions, whether they have the same or different denominators

Word Problem Solution Strategy

Systematic approach to solving fraction word problems, helping students identify the correct operation and organize their solution

Fractions — Operations, Conversion & Comparison is chapter 2 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.

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