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 7² and 8²?
- 2.A square garden has an area of 2500 square m. How long is each side (in m)?
- 3.What is 12²? =
- 4.What is √2401? =
- 5.What is √121? =
- 6.What is 52²? =
- 7.A square garden has an area of 2209 square m. How long is each side (in m)?
- 8.A square garden has an area of 625 square m. How long is each side (in m)?
- 9.What is the smallest whole number by which 27 must be divided to get a perfect square?
- 10.What is the sum of the first 12 odd numbers (1 + 3 + 5 + …)?
- 11.What is 40²? =
- 12.A square garden has an area of 3136 square m. How long is each side (in m)?
- 13.What is the smallest whole number by which 128 must be divided to get a perfect square?
- 14.What is the sum of the first 7 odd numbers (1 + 3 + 5 + …)?
- 15.How many whole numbers lie between 26² and 27²?
- 16.What is the sum of the first 11 odd numbers (1 + 3 + 5 + …)?
- 17.What is √484? =
- 18.What is the smallest whole number by which 32 must be divided to get a perfect square?
- 19.What is √784? =
- 20.Which of these is a perfect square? (a) 784 (b) 829 (c) 838
- 21.What is √400? =
- 22.What is 34²? =
- 23.How many whole numbers lie between 40² and 41²?
- 24.What is the sum of the first 27 odd numbers (1 + 3 + 5 + …)?
- 25.How many whole numbers lie between 29² and 30²?
- 26.Which of these is a perfect square? (a) 1156 (b) 1186 (c) 1215
- 27.What is 23²? =
- 28.How many whole numbers lie between 34² and 35²?
- 29.What is √324? =
- 30.What is 71²? =
- 31.What is the smallest whole number by which 24 must be multiplied to get a perfect square?
- 32.What is √5184? =
- 33.What is the smallest whole number by which 245 must be multiplied to get a perfect square?
- 34.What is 26²? =
- 35.What is the sum of the first 23 odd numbers (1 + 3 + 5 + …)?
- 36.What is 15²? =
- 37.How many whole numbers lie between 17² and 18²?
- 38.A square garden has an area of 3481 square m. How long is each side (in m)?
- 39.What is the sum of the first 14 odd numbers (1 + 3 + 5 + …)?
- 40.Which of these is a perfect square? (a) 100 (b) 104 (c) 119
Answer key
- 14
- 50
- 144
- 49
- 11
- 2704
- 47
- 25
- 3
- 144
- 1600
- 56
- 2
- 49
- 52
- 121
- 22
- 2
- 28
- 784
- 20
- 1156
- 80
- 729
- 58
- 1156
- 529
- 68
- 18
- 5041
- 6
- 72
- 5
- 676
- 529
- 225
- 34
- 59
- 196
- 100
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