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) 427 (b) 403 (c) 400
- 2.What is √2916? =
- 3.What is √1369? =
- 4.What is the smallest whole number by which 832 must be divided to get a perfect square?
- 5.How many whole numbers lie between 46² and 47²?
- 6.How many whole numbers lie between 23² and 24²?
- 7.What is √3600? =
- 8.What is 64²? =
- 9.A square garden has an area of 441 square m. How long is each side (in m)?
- 10.What is √3249? =
- 11.What is the sum of the first 27 odd numbers (1 + 3 + 5 + …)?
- 12.What is the smallest whole number by which 384 must be multiplied to get a perfect square?
- 13.What is 17²? =
- 14.A square garden has an area of 400 square m. How long is each side (in m)?
- 15.Which of these is a perfect square? (a) 900 (b) 934 (c) 930
- 16.Which of these is a perfect square? (a) 840 (b) 784 (c) 822
- 17.What is the smallest whole number by which 448 must be multiplied to get a perfect square?
- 18.What is 25²? =
- 19.What is 24²? =
- 20.What is the smallest whole number by which 72 must be multiplied to get a perfect square?
- 21.A square garden has an area of 2601 square m. How long is each side (in m)?
- 22.A square garden has an area of 3249 square m. How long is each side (in m)?
- 23.What is √169? =
- 24.A square garden has an area of 121 square m. How long is each side (in m)?
- 25.What is √9409? =
- 26.What is the sum of the first 25 odd numbers (1 + 3 + 5 + …)?
- 27.How many whole numbers lie between 17² and 18²?
- 28.Which of these is a perfect square? (a) 175 (b) 187 (c) 169
- 29.What is √784? =
- 30.What is √7569? =
- 31.Which of these is a perfect square? (a) 531 (b) 529 (c) 566
- 32.What is 31²? =
- 33.How many whole numbers lie between 21² and 22²?
- 34.What is the sum of the first 22 odd numbers (1 + 3 + 5 + …)?
- 35.What is √729? =
- 36.Which of these is a perfect square? (a) 625 (b) 632 (c) 649
- 37.Which of these is a perfect square? (a) 199 (b) 196 (c) 214
- 38.A square garden has an area of 25 square m. How long is each side (in m)?
- 39.A square garden has an area of 3025 square m. How long is each side (in m)?
- 40.What is the sum of the first 23 odd numbers (1 + 3 + 5 + …)?
Answer key
- 400
- 54
- 37
- 13
- 92
- 46
- 60
- 4096
- 21
- 57
- 729
- 6
- 289
- 20
- 900
- 784
- 7
- 625
- 576
- 2
- 51
- 57
- 13
- 11
- 97
- 625
- 34
- 169
- 28
- 87
- 529
- 961
- 42
- 484
- 27
- 625
- 196
- 5
- 55
- 529
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