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 √7225? =
- 2.What is the sum of the first 24 odd numbers (1 + 3 + 5 + …)?
- 3.What is √8836? =
- 4.What is 72²? =
- 5.Which of these is a perfect square? (a) 452 (b) 441 (c) 458
- 6.What is the smallest whole number by which 128 must be multiplied to get a perfect square?
- 7.A square garden has an area of 2401 square m. How long is each side (in m)?
- 8.What is √3969? =
- 9.A square garden has an area of 169 square m. How long is each side (in m)?
- 10.A square garden has an area of 64 square m. How long is each side (in m)?
- 11.What is √625? =
- 12.Which of these is a perfect square? (a) 1600 (b) 1635 (c) 1660
- 13.How many whole numbers lie between 48² and 49²?
- 14.How many whole numbers lie between 45² and 46²?
- 15.How many whole numbers lie between 16² and 17²?
- 16.What is 36²? =
- 17.What is the sum of the first 17 odd numbers (1 + 3 + 5 + …)?
- 18.What is the sum of the first 20 odd numbers (1 + 3 + 5 + …)?
- 19.Which of these is a perfect square? (a) 1119 (b) 1116 (c) 1089
- 20.What is the smallest whole number by which 192 must be multiplied to get a perfect square?
- 21.What is 26²? =
- 22.What is 13²? =
- 23.What is 16²? =
- 24.What is the sum of the first 25 odd numbers (1 + 3 + 5 + …)?
- 25.What is 98²? =
- 26.Which of these is a perfect square? (a) 301 (b) 289 (c) 309
- 27.What is the sum of the first 22 odd numbers (1 + 3 + 5 + …)?
- 28.What is the smallest whole number by which 24 must be multiplied to get a perfect square?
- 29.What is √7396? =
- 30.A square garden has an area of 2704 square m. How long is each side (in m)?
- 31.What is the sum of the first 8 odd numbers (1 + 3 + 5 + …)?
- 32.How many whole numbers lie between 29² and 30²?
- 33.What is 30²? =
- 34.Which of these is a perfect square? (a) 1296 (b) 1368 (c) 1315
- 35.What is 34²? =
- 36.What is the smallest whole number by which 99 must be multiplied to get a perfect square?
- 37.How many whole numbers lie between 41² and 42²?
- 38.What is 60²? =
- 39.What is 64²? =
- 40.A square garden has an area of 100 square m. How long is each side (in m)?
Answer key
- 85
- 576
- 94
- 5184
- 441
- 2
- 49
- 63
- 13
- 8
- 25
- 1600
- 96
- 90
- 32
- 1296
- 289
- 400
- 1089
- 3
- 676
- 169
- 256
- 625
- 9604
- 289
- 484
- 6
- 86
- 52
- 64
- 58
- 900
- 1296
- 1156
- 11
- 82
- 3600
- 4096
- 10
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