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 √225? =
- 2.Which of these is a perfect square? (a) 359 (b) 331 (c) 324
- 3.What is 57²? =
- 4.What is 50²? =
- 5.What is 42²? =
- 6.What is the smallest whole number by which 160 must be divided to get a perfect square?
- 7.A square garden has an area of 3600 square m. How long is each side (in m)?
- 8.Which of these is a perfect square? (a) 1035 (b) 1037 (c) 1024
- 9.Which of these is a perfect square? (a) 1211 (b) 1196 (c) 1156
- 10.What is √3025? =
- 11.What is the sum of the first 14 odd numbers (1 + 3 + 5 + …)?
- 12.What is √5041? =
- 13.How many whole numbers lie between 29² and 30²?
- 14.What is 49²? =
- 15.A square garden has an area of 100 square m. How long is each side (in m)?
- 16.How many whole numbers lie between 28² and 29²?
- 17.What is √5184? =
- 18.How many whole numbers lie between 45² and 46²?
- 19.A square garden has an area of 64 square m. How long is each side (in m)?
- 20.What is √576? =
- 21.What is the sum of the first 15 odd numbers (1 + 3 + 5 + …)?
- 22.What is √900? =
- 23.What is 40²? =
- 24.What is the smallest whole number by which 27 must be divided to get a perfect square?
- 25.How many whole numbers lie between 40² and 41²?
- 26.How many whole numbers lie between 44² and 45²?
- 27.Which of these is a perfect square? (a) 289 (b) 320 (c) 298
- 28.What is √3249? =
- 29.What is 25²? =
- 30.What is 80²? =
- 31.A square garden has an area of 484 square m. How long is each side (in m)?
- 32.What is 35²? =
- 33.Which of these is a perfect square? (a) 1133 (b) 1135 (c) 1089
- 34.What is 23²? =
- 35.How many whole numbers lie between 10² and 11²?
- 36.What is √3844? =
- 37.What is the smallest whole number by which 20 must be multiplied to get a perfect square?
- 38.How many whole numbers lie between 49² and 50²?
- 39.What is the smallest whole number by which 810 must be divided to get a perfect square?
- 40.What is the smallest whole number by which 108 must be divided to get a perfect square?
Answer key
- 15
- 324
- 3249
- 2500
- 1764
- 10
- 60
- 1024
- 1156
- 55
- 196
- 71
- 58
- 2401
- 10
- 56
- 72
- 90
- 8
- 24
- 225
- 30
- 1600
- 3
- 80
- 88
- 289
- 57
- 625
- 6400
- 22
- 1225
- 1089
- 529
- 20
- 62
- 5
- 98
- 10
- 3
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