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 smallest whole number by which 490 must be multiplied to get a perfect square?
- 2.A square garden has an area of 784 square m. How long is each side (in m)?
- 3.What is the sum of the first 6 odd numbers (1 + 3 + 5 + …)?
- 4.What is √6400? =
- 5.What is the sum of the first 10 odd numbers (1 + 3 + 5 + …)?
- 6.What is 59²? =
- 7.How many whole numbers lie between 46² and 47²?
- 8.A square garden has an area of 1849 square m. How long is each side (in m)?
- 9.A square garden has an area of 1296 square m. How long is each side (in m)?
- 10.What is √9025? =
- 11.What is 49²? =
- 12.How many whole numbers lie between 13² and 14²?
- 13.A square garden has an area of 3025 square m. How long is each side (in m)?
- 14.What is the smallest whole number by which 12 must be divided to get a perfect square?
- 15.A square garden has an area of 1764 square m. How long is each side (in m)?
- 16.What is √7396? =
- 17.Which of these is a perfect square? (a) 523 (b) 484 (c) 509
- 18.What is √7569? =
- 19.Which of these is a perfect square? (a) 720 (b) 725 (c) 676
- 20.What is the smallest whole number by which 325 must be divided to get a perfect square?
- 21.What is √625? =
- 22.What is 75²? =
- 23.What is the sum of the first 12 odd numbers (1 + 3 + 5 + …)?
- 24.How many whole numbers lie between 32² and 33²?
- 25.What is 68²? =
- 26.Which of these is a perfect square? (a) 324 (b) 347 (c) 340
- 27.How many whole numbers lie between 30² and 31²?
- 28.What is the sum of the first 21 odd numbers (1 + 3 + 5 + …)?
- 29.Which of these is a perfect square? (a) 1604 (b) 1626 (c) 1600
- 30.A square garden has an area of 1024 square m. How long is each side (in m)?
- 31.What is 37²? =
- 32.What is 55²? =
- 33.Which of these is a perfect square? (a) 806 (b) 788 (c) 784
- 34.What is the smallest whole number by which 99 must be multiplied to get a perfect square?
- 35.Which of these is a perfect square? (a) 961 (b) 989 (c) 980
- 36.What is √1849? =
- 37.Which of these is a perfect square? (a) 400 (b) 434 (c) 402
- 38.How many whole numbers lie between 11² and 12²?
- 39.What is 23²? =
- 40.What is the sum of the first 19 odd numbers (1 + 3 + 5 + …)?
Answer key
- 10
- 28
- 36
- 80
- 100
- 3481
- 92
- 43
- 36
- 95
- 2401
- 26
- 55
- 3
- 42
- 86
- 484
- 87
- 676
- 13
- 25
- 5625
- 144
- 64
- 4624
- 324
- 60
- 441
- 1600
- 32
- 1369
- 3025
- 784
- 11
- 961
- 43
- 400
- 22
- 529
- 361
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