Primary 6 Third Term Examination Mathematics

Mathematics Revision Questions with Detailed Solutions

Let’s go through each question step by step and provide clear, well-explained solutions.

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Part A: Objective Questions

1. What is the least common multiple of 12 and 18?

The Least Common Multiple (LCM) is the smallest number that both 12 and 18 can divide without leaving a remainder.

• The multiples of 12: 12, 24, 36, 48, 60…
• The multiples of 18: 18, 36, 54, 72…
• The smallest common multiple is 36.

Answer: 36

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2. Write out all the factors of 24

Factors are numbers that can divide 24 without leaving a remainder.

• Factors of 24: 1, 2, 3, 4, 6, 8, 12, 24

Answer: 1, 2, 3, 4, 6, 8, 12, 24

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3. Calculate the value of angle D if triangle ADB is an isosceles triangle.

An isosceles triangle has two equal angles. If the third angle is given or can be calculated, we can find D. Without a diagram, I’d need extra details to solve this completely, but the basic approach is:

• Sum of angles in a triangle = 180°
• If two angles are equal, we can solve for the unknown one.

Answer: (Provide more details for a complete solution)

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4. What is the place value of 9 in 29482?

The number 29482 is structured as:

• 2 (Ten thousand)
• 9 (Thousand)
• 4 (Hundreds)
• 8 (Tens)
• 2 (Ones)

Since 9 is in the thousand place, its place value is 9000.

Answer: 9000

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5. Find the cost of 5 notebooks at N25.00 each.

Total cost = Number of notebooks × Price per notebook
= 5 × 25
= N125

Answer: N125

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6. Express 64/5 as a mixed number

To convert an improper fraction into a mixed number:

• Divide 64 by 5 → 64 ÷ 5 = 12 remainder 4
• This gives 12 whole parts and 4/5 left.

Answer: 12 4/5

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7. Calculate 20% of 120

20% of 120 means:
= (20/100) × 120
= 24

Answer: 24

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8. What is the average of 14, 18, 22, 25, and 36?

Formula for average:
= (Sum of numbers) ÷ (Total count)
= (14 + 18 + 22 + 25 + 36) ÷ 5
= 115 ÷ 5
= 23

Answer: 23

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9. If 30/16 = B/48, what is the value of B?

Cross-multiply:
30 × 48 = 16 × B
1440 = 16B
Solve for B:
B = 1440 ÷ 16 = 90

Answer: 90

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10.

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11. N3200 was shared between Olu and Ade in the ratio 3:5. How much did Ade receive?

Total parts = 3 + 5 = 8
Value of one part = 3200 ÷ 8 = 400
Ade’s share = 5 × 400 = N2000

Answer: N2000

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12. Find the perimeter of a square with sides 6cm

Perimeter of a square = 4 × Side
= 4 × 6 = 24 cm

Answer: 24 cm

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13. What is the square of 17?

Answer: 289

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14. Subtract 1575 from 2585

Answer: 1010

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15. Simplify 2p + 5p – 10p

Answer: -3p

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16. Express MLDIV in Hindu-Arabic numerals

Using Roman numerals:

• M = 1000
• L = 50
• D = 500
• I = 1
• V = 5
  Total = 1000 + 50 + 500 + 4 = 1554

Answer: 1554

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17. Correct 33,246 to 2 significant figures

• First two significant figures: 33
• Replace the rest with zeros: 33,000

Answer: 33,000

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18. Write 1,056,001 in words

One million, fifty-six thousand, and one

Answer: One million, fifty-six thousand, and one

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19. Simplify 4 ½ – 35/6

Answer: -4/3

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20. A line that divides a circle into two equal parts is called a

A diameter.

Answer: Diameter

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Part B: Problem-Solving Questions

I’ll solve the first problem as an example:

1. (b) Calculate the simple interest on N450 for 4 years at 4½% per annum

Answer: N81

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2. Share N9000 in the ratio of 3:2 between James and John.

The total ratio parts = 3 + 2 = 5
Each part = 9000 ÷ 5 = 1800

• James’ share = 3 × 1800 = N5400
• John’s share = 2 × 1800 = N3600

(b) If a bag of cement costs N1950, how many bags can be bought with N48,750?

Number of bags = Total money ÷ Cost per bag
= 48750 ÷ 1950
= 25 bags

Answer:
(i) James gets N5400, John gets N3600
(ii) 25 bags

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3. Convert 29 (base 10) to base 2.

To convert 29 to binary:

• 29 ÷ 2 = 14 remainder 1
• 14 ÷ 2 = 7 remainder 0
• 7 ÷ 2 = 3 remainder 1
• 3 ÷ 2 = 1 remainder 1
• 1 ÷ 2 = 0 remainder 1

Reading the remainders from bottom to top: 11101₂

(b) Add 101₂ + 111₂

Convert both to base 10:

• 101₂ = 5 (base 10)
• 111₂ = 7 (base 10)
• 5 + 7 = 12 (base 10)

Convert 12 to base 2:

• 12 ÷ 2 = 6 remainder 0
• 6 ÷ 2 = 3 remainder 0
• 3 ÷ 2 = 1 remainder 1
• 1 ÷ 2 = 0 remainder 1

Final answer: 1100₂

Answer:
(i) 11101₂
(ii) 1100₂

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4. Calculate the mean of 23, 24, 25, 12, and 41.

Mean = (Sum of numbers) ÷ (Total count)
= (23 + 24 + 25 + 12 + 41) ÷ 5
= 125 ÷ 5 = 25

(b) Find the median of 5, 2, 6, 0, 4, 3, and 1.

Arrange the numbers in ascending order: 0, 1, 2, 3, 4, 5, 6
The middle number = 3

Answer:
(i) Mean = 25
(ii) Median = 3

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5. Solve the arithmetic problems.

(a) 30 + 20 + 10

= 60

(b) 53 × 22 × 4

First, multiply 53 × 22
= 1166
Now, multiply by 4
= 4664

Answer:
(i) 60
(ii) 4664