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.A square garden has an area of 1764 square m. How long is each side (in m)?
- 2.What is 31²? =
- 3.What is the sum of the first 23 odd numbers (1 + 3 + 5 + …)?
- 4.What is 15²? =
- 5.A square garden has an area of 400 square m. How long is each side (in m)?
- 6.Which of these is a perfect square? (a) 862 (b) 847 (c) 841
- 7.Which of these is a perfect square? (a) 1363 (b) 1335 (c) 1296
- 8.What is the sum of the first 5 odd numbers (1 + 3 + 5 + …)?
- 9.What is √1936? =
- 10.What is the smallest whole number by which 20 must be divided to get a perfect square?
- 11.What is the smallest whole number by which 216 must be multiplied to get a perfect square?
- 12.A square garden has an area of 289 square m. How long is each side (in m)?
- 13.What is the smallest whole number by which 24 must be divided to get a perfect square?
- 14.Which of these is a perfect square? (a) 784 (b) 835 (c) 823
- 15.What is the smallest whole number by which 640 must be divided to get a perfect square?
- 16.What is √484? =
- 17.What is the sum of the first 30 odd numbers (1 + 3 + 5 + …)?
- 18.What is √289? =
- 19.What is 63²? =
- 20.How many whole numbers lie between 43² and 44²?
- 21.What is the smallest whole number by which 98 must be multiplied to get a perfect square?
- 22.What is the smallest whole number by which 350 must be divided to get a perfect square?
- 23.A square garden has an area of 784 square m. How long is each side (in m)?
- 24.What is the smallest whole number by which 112 must be multiplied to get a perfect square?
- 25.What is 26²? =
- 26.How many whole numbers lie between 39² and 40²?
- 27.A square garden has an area of 3364 square m. How long is each side (in m)?
- 28.What is the smallest whole number by which 126 must be divided to get a perfect square?
- 29.How many whole numbers lie between 5² and 6²?
- 30.Which of these is a perfect square? (a) 579 (b) 618 (c) 576
- 31.What is the smallest whole number by which 1053 must be divided to get a perfect square?
- 32.Which of these is a perfect square? (a) 441 (b) 445 (c) 453
- 33.A square garden has an area of 1444 square m. How long is each side (in m)?
- 34.What is √1600? =
- 35.What is √9409? =
- 36.What is 21²? =
- 37.What is the sum of the first 13 odd numbers (1 + 3 + 5 + …)?
- 38.What is √5929? =
- 39.How many whole numbers lie between 16² and 17²?
- 40.What is √2601? =
Answer key
- 42
- 961
- 529
- 225
- 20
- 841
- 1296
- 25
- 44
- 5
- 6
- 17
- 6
- 784
- 10
- 22
- 900
- 17
- 3969
- 86
- 2
- 14
- 28
- 7
- 676
- 78
- 58
- 14
- 10
- 576
- 13
- 441
- 38
- 40
- 97
- 441
- 169
- 77
- 32
- 51
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