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 √361? =
- 2.What is √4624? =
- 3.A square garden has an area of 3481 square m. How long is each side (in m)?
- 4.How many whole numbers lie between 20² and 21²?
- 5.Which of these is a perfect square? (a) 474 (b) 441 (c) 442
- 6.What is 74²? =
- 7.What is the smallest whole number by which 135 must be divided to get a perfect square?
- 8.What is the sum of the first 19 odd numbers (1 + 3 + 5 + …)?
- 9.What is 38²? =
- 10.What is the sum of the first 16 odd numbers (1 + 3 + 5 + …)?
- 11.Which of these is a perfect square? (a) 324 (b) 338 (c) 334
- 12.What is the sum of the first 20 odd numbers (1 + 3 + 5 + …)?
- 13.How many whole numbers lie between 35² and 36²?
- 14.What is the sum of the first 23 odd numbers (1 + 3 + 5 + …)?
- 15.What is the sum of the first 13 odd numbers (1 + 3 + 5 + …)?
- 16.How many whole numbers lie between 16² and 17²?
- 17.What is 49²? =
- 18.Which of these is a perfect square? (a) 286 (b) 264 (c) 256
- 19.What is √5184? =
- 20.How many whole numbers lie between 37² and 38²?
- 21.What is √9216? =
- 22.What is the sum of the first 5 odd numbers (1 + 3 + 5 + …)?
- 23.What is 57²? =
- 24.What is the smallest whole number by which 8 must be multiplied to get a perfect square?
- 25.What is the smallest whole number by which 810 must be multiplied to get a perfect square?
- 26.What is 15²? =
- 27.What is the smallest whole number by which 80 must be multiplied to get a perfect square?
- 28.How many whole numbers lie between 15² and 16²?
- 29.What is the sum of the first 10 odd numbers (1 + 3 + 5 + …)?
- 30.A square garden has an area of 625 square m. How long is each side (in m)?
- 31.What is √196? =
- 32.A square garden has an area of 784 square m. How long is each side (in m)?
- 33.A square garden has an area of 961 square m. How long is each side (in m)?
- 34.What is the smallest whole number by which 52 must be multiplied to get a perfect square?
- 35.How many whole numbers lie between 50² and 51²?
- 36.What is the sum of the first 11 odd numbers (1 + 3 + 5 + …)?
- 37.A square garden has an area of 121 square m. How long is each side (in m)?
- 38.What is √729? =
- 39.What is √8464? =
- 40.What is √1764? =
Answer key
- 19
- 68
- 59
- 40
- 441
- 5476
- 15
- 361
- 1444
- 256
- 324
- 400
- 70
- 529
- 169
- 32
- 2401
- 256
- 72
- 74
- 96
- 25
- 3249
- 2
- 10
- 225
- 5
- 30
- 100
- 25
- 14
- 28
- 31
- 13
- 100
- 121
- 11
- 27
- 92
- 42
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