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.Which of these is a perfect square? (a) 1369 (b) 1413 (c) 1391
- 2.What is 53²? =
- 3.What is the smallest whole number by which 325 must be divided to get a perfect square?
- 4.What is the smallest whole number by which 18 must be multiplied to get a perfect square?
- 5.What is the sum of the first 21 odd numbers (1 + 3 + 5 + …)?
- 6.What is √7225? =
- 7.A square garden has an area of 289 square m. How long is each side (in m)?
- 8.What is 92²? =
- 9.What is the sum of the first 15 odd numbers (1 + 3 + 5 + …)?
- 10.Which of these is a perfect square? (a) 961 (b) 1009 (c) 1008
- 11.What is the sum of the first 14 odd numbers (1 + 3 + 5 + …)?
- 12.A square garden has an area of 1936 square m. How long is each side (in m)?
- 13.What is 21²? =
- 14.How many whole numbers lie between 49² and 50²?
- 15.What is 78²? =
- 16.What is 16²? =
- 17.A square garden has an area of 324 square m. How long is each side (in m)?
- 18.What is the sum of the first 19 odd numbers (1 + 3 + 5 + …)?
- 19.What is the sum of the first 10 odd numbers (1 + 3 + 5 + …)?
- 20.What is √7056? =
- 21.What is the smallest whole number by which 98 must be multiplied to get a perfect square?
- 22.Which of these is a perfect square? (a) 397 (b) 382 (c) 361
- 23.A square garden has an area of 2916 square m. How long is each side (in m)?
- 24.What is √676? =
- 25.What is √1296? =
- 26.How many whole numbers lie between 38² and 39²?
- 27.How many whole numbers lie between 33² and 34²?
- 28.What is the smallest whole number by which 891 must be divided to get a perfect square?
- 29.What is the smallest whole number by which 832 must be multiplied to get a perfect square?
- 30.A square garden has an area of 36 square m. How long is each side (in m)?
- 31.Which of these is a perfect square? (a) 145 (b) 144 (c) 147
- 32.What is √1681? =
- 33.A square garden has an area of 121 square m. How long is each side (in m)?
- 34.A square garden has an area of 256 square m. How long is each side (in m)?
- 35.What is √2704? =
- 36.What is the smallest whole number by which 224 must be divided to get a perfect square?
- 37.What is 26²? =
- 38.Which of these is a perfect square? (a) 316 (b) 295 (c) 289
- 39.What is the smallest whole number by which 735 must be divided to get a perfect square?
- 40.What is √9604? =
Answer key
- 1369
- 2809
- 13
- 2
- 441
- 85
- 17
- 8464
- 225
- 961
- 196
- 44
- 441
- 98
- 6084
- 256
- 18
- 361
- 100
- 84
- 2
- 361
- 54
- 26
- 36
- 76
- 66
- 11
- 13
- 6
- 144
- 41
- 11
- 16
- 52
- 14
- 676
- 289
- 15
- 98
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