5th Grade Maths on Major Topics

There are 264 pupils in a school. If 3/8 of them are girls, how many are boys?

• 165
• 99
• 164
• 90

Answer explanation

First find the number of girls: (3/8) * 264 = 99 girls. Then subtract from the total to find the boys: 264 - 99 = 165 boys. Alternatively, find the fraction of boys: 1 - 3/8 = 5/8. Then calculate the number of boys: (5/8) * 264 = 165.

Put a decimal point in the number 98675 so that the digit 7 will have the value of thousandths.

• 9.8675
• 98.675
• 986.75
• 9867.5

Answer explanation

The thousandths place is the third digit after the decimal point. Placing the decimal after 98 makes the 6 tenths, 7 hundredths. Placing it after 98 makes 6 tenths, 7 hundredths, and 5 thousandths. So 98.675 is correct.

Find the next two numbers in the sequence: 1.25, 1.90, 2.55, _____, _____.

• 2.90, 3.25
• 3.20, 3.85
• 3.00, 3.25
• 2.00, 3.00

Answer explanation

The difference between consecutive numbers is 1.90 - 1.25 = 0.65. So, the next numbers are 2.55 + 0.65 = 3.20 and 3.20 + 0.65 = 3.85.

What is the area of a rectangular board that has a perimeter of 36m and a breadth of 8m?

• 80 cm²
• 10 m²
• 800 m²
• 80 m²

Answer explanation

Perimeter = 2(Length + Breadth). 36 = 2(L + 8). 18 = L + 8. So, Length = 10m. Area = Length * Breadth = 10m * 8m = 80 m².

There are 720 books in a school library. If John has read 7/15 of them, how many books has he read?

• 620
• 336
• 520
• 500

Answer explanation

To find the number of books read, calculate (7/15) * 720. (720 / 15) = 48. Then, 48 * 7 = 336.

What is the Roman numeral for 99?

• IC
• XCIX
• LXXXXIX
• IM

Answer explanation

90 is XC (10 before 100) and 9 is IX (1 before 10). So, 99 is XCIX.

How is the number 54 written in Roman numerals?

• LIV
• VIV
• LIIII
• VL

Answer explanation

50 is L and 4 is IV. So, 54 is LIV.

What number does the Roman numeral CDXLIV represent?

• 444
• 644
• 464
• 544

Answer explanation

CD is 400 (100 before 500), XL is 40 (10 before 50), and IV is 4. So, 400 + 40 + 4 = 444.

Which of these Roman numerals is written incorrectly?

• IX
• XL
• VC
• XC

Answer explanation

You cannot subtract V, L, or D from a larger numeral. C should be subtracted from D or M. The correct way to write 95 would be XCV.

What is the value of CXX + XV?

• 135
• 125
• 115
• 105

Answer explanation

CXX is 120 and XV is 15. 120 + 15 = 135.