Class 8 Maths Worksheet: Squares and Square Roots
The method (Pairs make squares): Square: n × n. Quick way: (a + b)² = a² + 2ab + b², e.g. 42² = 1600 + 160 + 4. Square root: the number that times itself gives the square; a square ending in 4 has a root ending in 2 or 8. Make a perfect square: break into primes; multiply (or divide) by the prime left without a partner. 1 + 3 + 5 + … (n odd numbers) = n². Between n² and (n + 1)² there are 2n whole numbers.
NameDateTime takenScore ___ / 40
- 1.What is 17²? =
- 2.What is the smallest whole number by which 832 must be multiplied to get a perfect square?
- 3.What is the sum of the first 29 odd numbers (1 + 3 + 5 + …)?
- 4.What is the smallest whole number by which 1134 must be multiplied to get a perfect square?
- 5.Which of these is a perfect square? (a) 339 (b) 324 (c) 330
- 6.What is the sum of the first 12 odd numbers (1 + 3 + 5 + …)?
- 7.A square garden has an area of 961 square m. How long is each side (in m)?
- 8.What is √400? =
- 9.What is the smallest whole number by which 250 must be multiplied to get a perfect square?
- 10.A square garden has an area of 36 square m. How long is each side (in m)?
- 11.What is the sum of the first 7 odd numbers (1 + 3 + 5 + …)?
- 12.What is the smallest whole number by which 96 must be multiplied to get a perfect square?
- 13.What is √625? =
- 14.What is the smallest whole number by which 810 must be multiplied to get a perfect square?
- 15.What is √784? =
- 16.What is 12²? =
- 17.Which of these is a perfect square? (a) 132 (b) 130 (c) 121
- 18.What is 54²? =
- 19.Which of these is a perfect square? (a) 171 (b) 175 (c) 169
- 20.What is the smallest whole number by which 275 must be multiplied to get a perfect square?
- 21.A square garden has an area of 169 square m. How long is each side (in m)?
- 22.How many whole numbers lie between 29² and 30²?
- 23.What is 51²? =
- 24.How many whole numbers lie between 31² and 32²?
- 25.A square garden has an area of 784 square m. How long is each side (in m)?
- 26.What is the sum of the first 26 odd numbers (1 + 3 + 5 + …)?
- 27.What is the sum of the first 21 odd numbers (1 + 3 + 5 + …)?
- 28.Which of these is a perfect square? (a) 720 (b) 727 (c) 676
- 29.A square garden has an area of 400 square m. How long is each side (in m)?
- 30.What is 98²? =
- 31.What is the smallest whole number by which 350 must be divided to get a perfect square?
- 32.How many whole numbers lie between 44² and 45²?
- 33.What is the smallest whole number by which 20 must be multiplied to get a perfect square?
- 34.What is 45²? =
- 35.What is the smallest whole number by which 640 must be divided to get a perfect square?
- 36.What is 65²? =
- 37.How many whole numbers lie between 16² and 17²?
- 38.Which of these is a perfect square? (a) 734 (b) 729 (c) 735
- 39.What is the smallest whole number by which 350 must be multiplied to get a perfect square?
- 40.What is the smallest whole number by which 325 must be multiplied to get a perfect square?
Answer key
- 289
- 13
- 841
- 14
- 324
- 144
- 31
- 20
- 10
- 6
- 49
- 6
- 25
- 10
- 28
- 144
- 121
- 2916
- 169
- 11
- 13
- 58
- 2601
- 62
- 28
- 676
- 441
- 676
- 20
- 9604
- 14
- 88
- 5
- 2025
- 10
- 4225
- 32
- 729
- 14
- 13
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