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.How many whole numbers lie between 20² and 21²?
- 2.A square garden has an area of 576 square m. How long is each side (in m)?
- 3.A square garden has an area of 1024 square m. How long is each side (in m)?
- 4.Which of these is a perfect square? (a) 663 (b) 674 (c) 625
- 5.What is √9025? =
- 6.What is √2304? =
- 7.A square garden has an area of 289 square m. How long is each side (in m)?
- 8.What is the smallest whole number by which 48 must be divided to get a perfect square?
- 9.What is the smallest whole number by which 96 must be multiplied to get a perfect square?
- 10.A square garden has an area of 64 square m. How long is each side (in m)?
- 11.What is the smallest whole number by which 1053 must be multiplied to get a perfect square?
- 12.What is √1089? =
- 13.A square garden has an area of 3249 square m. How long is each side (in m)?
- 14.What is the smallest whole number by which 147 must be divided to get a perfect square?
- 15.What is the smallest whole number by which 18 must be divided to get a perfect square?
- 16.How many whole numbers lie between 50² and 51²?
- 17.What is √5184? =
- 18.What is √6241? =
- 19.What is 14²? =
- 20.What is the smallest whole number by which 350 must be multiplied to get a perfect square?
- 21.What is the sum of the first 23 odd numbers (1 + 3 + 5 + …)?
- 22.What is the smallest whole number by which 72 must be multiplied to get a perfect square?
- 23.How many whole numbers lie between 43² and 44²?
- 24.A square garden has an area of 1369 square m. How long is each side (in m)?
- 25.A square garden has an area of 121 square m. How long is each side (in m)?
- 26.What is √3249? =
- 27.What is √1369? =
- 28.How many whole numbers lie between 32² and 33²?
- 29.What is 70²? =
- 30.What is 65²? =
- 31.What is √2401? =
- 32.What is the sum of the first 20 odd numbers (1 + 3 + 5 + …)?
- 33.Which of these is a perfect square? (a) 683 (b) 708 (c) 676
- 34.A square garden has an area of 169 square m. How long is each side (in m)?
- 35.Which of these is a perfect square? (a) 283 (b) 265 (c) 256
- 36.What is √3364? =
- 37.What is the smallest whole number by which 20 must be multiplied to get a perfect square?
- 38.What is the smallest whole number by which 384 must be multiplied to get a perfect square?
- 39.What is √841? =
- 40.What is the smallest whole number by which 125 must be divided to get a perfect square?
Answer key
- 40
- 24
- 32
- 625
- 95
- 48
- 17
- 3
- 6
- 8
- 13
- 33
- 57
- 3
- 2
- 100
- 72
- 79
- 196
- 14
- 529
- 2
- 86
- 37
- 11
- 57
- 37
- 64
- 4900
- 4225
- 49
- 400
- 676
- 13
- 256
- 58
- 5
- 6
- 29
- 5
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