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 the sum of the first 22 odd numbers (1 + 3 + 5 + …)?
- 2.What is 50²? =
- 3.What is 58²? =
- 4.What is the smallest whole number by which 375 must be multiplied to get a perfect square?
- 5.What is √169? =
- 6.Which of these is a perfect square? (a) 344 (b) 324 (c) 335
- 7.How many whole numbers lie between 42² and 43²?
- 8.What is the sum of the first 6 odd numbers (1 + 3 + 5 + …)?
- 9.How many whole numbers lie between 7² and 8²?
- 10.What is 40²? =
- 11.A square garden has an area of 576 square m. How long is each side (in m)?
- 12.How many whole numbers lie between 17² and 18²?
- 13.What is 23²? =
- 14.What is the smallest whole number by which 405 must be multiplied to get a perfect square?
- 15.How many whole numbers lie between 24² and 25²?
- 16.What is 26²? =
- 17.How many whole numbers lie between 10² and 11²?
- 18.How many whole numbers lie between 9² and 10²?
- 19.How many whole numbers lie between 22² and 23²?
- 20.What is √2601? =
- 21.What is 76²? =
- 22.Which of these is a perfect square? (a) 529 (b) 560 (c) 540
- 23.What is √676? =
- 24.What is the smallest whole number by which 216 must be divided to get a perfect square?
- 25.What is √144? =
- 26.How many whole numbers lie between 16² and 17²?
- 27.What is the sum of the first 25 odd numbers (1 + 3 + 5 + …)?
- 28.What is 87²? =
- 29.What is √361? =
- 30.What is the sum of the first 11 odd numbers (1 + 3 + 5 + …)?
- 31.What is 21²? =
- 32.What is the smallest whole number by which 539 must be multiplied to get a perfect square?
- 33.Which of these is a perfect square? (a) 361 (b) 380 (c) 378
- 34.A square garden has an area of 64 square m. How long is each side (in m)?
- 35.What is √5929? =
- 36.A square garden has an area of 676 square m. How long is each side (in m)?
- 37.A square garden has an area of 2304 square m. How long is each side (in m)?
- 38.What is 13²? =
- 39.What is √4900? =
- 40.What is √729? =
Answer key
- 484
- 2500
- 3364
- 15
- 13
- 324
- 84
- 36
- 14
- 1600
- 24
- 34
- 529
- 5
- 48
- 676
- 20
- 18
- 44
- 51
- 5776
- 529
- 26
- 6
- 12
- 32
- 625
- 7569
- 19
- 121
- 441
- 11
- 361
- 8
- 77
- 26
- 48
- 169
- 70
- 27
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