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.How many whole numbers lie between 28² and 29²?
- 2.What is 66²? =
- 3.What is √9604? =
- 4.What is the smallest whole number by which 117 must be multiplied to get a perfect square?
- 5.What is 72²? =
- 6.Which of these is a perfect square? (a) 1296 (b) 1328 (c) 1332
- 7.What is the sum of the first 8 odd numbers (1 + 3 + 5 + …)?
- 8.A square garden has an area of 1681 square m. How long is each side (in m)?
- 9.What is √6241? =
- 10.What is the sum of the first 28 odd numbers (1 + 3 + 5 + …)?
- 11.What is √7225? =
- 12.A square garden has an area of 1849 square m. How long is each side (in m)?
- 13.What is 68²? =
- 14.A square garden has an area of 676 square m. How long is each side (in m)?
- 15.What is the smallest whole number by which 350 must be divided to get a perfect square?
- 16.What is the smallest whole number by which 208 must be divided to get a perfect square?
- 17.What is 58²? =
- 18.What is 86²? =
- 19.What is √169? =
- 20.What is √4900? =
- 21.How many whole numbers lie between 20² and 21²?
- 22.What is the sum of the first 15 odd numbers (1 + 3 + 5 + …)?
- 23.What is 18²? =
- 24.Which of these is a perfect square? (a) 1050 (b) 1024 (c) 1054
- 25.Which of these is a perfect square? (a) 185 (b) 187 (c) 169
- 26.Which of these is a perfect square? (a) 905 (b) 903 (c) 900
- 27.What is the smallest whole number by which 1215 must be multiplied to get a perfect square?
- 28.What is √1296? =
- 29.How many whole numbers lie between 15² and 16²?
- 30.A square garden has an area of 441 square m. How long is each side (in m)?
- 31.Which of these is a perfect square? (a) 829 (b) 793 (c) 784
- 32.Which of these is a perfect square? (a) 1103 (b) 1098 (c) 1089
- 33.What is the smallest whole number by which 18 must be multiplied to get a perfect square?
- 34.What is √289? =
- 35.What is √4356? =
- 36.What is √625? =
- 37.How many whole numbers lie between 45² and 46²?
- 38.What is the smallest whole number by which 150 must be divided to get a perfect square?
- 39.What is √5476? =
- 40.How many whole numbers lie between 6² and 7²?
Answer key
- 56
- 4356
- 98
- 13
- 5184
- 1296
- 64
- 41
- 79
- 784
- 85
- 43
- 4624
- 26
- 14
- 13
- 3364
- 7396
- 13
- 70
- 40
- 225
- 324
- 1024
- 169
- 900
- 15
- 36
- 30
- 21
- 784
- 1089
- 2
- 17
- 66
- 25
- 90
- 6
- 74
- 12
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