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 8² and 9²?
- 2.What is 20²? =
- 3.Which of these is a perfect square? (a) 253 (b) 225 (c) 254
- 4.What is 73²? =
- 5.Which of these is a perfect square? (a) 256 (b) 260 (c) 258
- 6.Which of these is a perfect square? (a) 1676 (b) 1636 (c) 1600
- 7.What is 45²? =
- 8.What is 91²? =
- 9.What is 80²? =
- 10.How many whole numbers lie between 37² and 38²?
- 11.How many whole numbers lie between 49² and 50²?
- 12.Which of these is a perfect square? (a) 1300 (b) 1296 (c) 1322
- 13.A square garden has an area of 961 square m. How long is each side (in m)?
- 14.What is the sum of the first 25 odd numbers (1 + 3 + 5 + …)?
- 15.What is √7056? =
- 16.What is the sum of the first 28 odd numbers (1 + 3 + 5 + …)?
- 17.Which of these is a perfect square? (a) 174 (b) 189 (c) 169
- 18.What is 17²? =
- 19.What is the smallest whole number by which 63 must be divided to get a perfect square?
- 20.What is the sum of the first 8 odd numbers (1 + 3 + 5 + …)?
- 21.What is the smallest whole number by which 448 must be multiplied to get a perfect square?
- 22.How many whole numbers lie between 36² and 37²?
- 23.A square garden has an area of 1521 square m. How long is each side (in m)?
- 24.What is 60²? =
- 25.A square garden has an area of 2025 square m. How long is each side (in m)?
- 26.Which of these is a perfect square? (a) 301 (b) 304 (c) 289
- 27.What is 93²? =
- 28.How many whole numbers lie between 40² and 41²?
- 29.Which of these is a perfect square? (a) 114 (b) 100 (c) 120
- 30.What is √2704? =
- 31.What is √256? =
- 32.Which of these is a perfect square? (a) 374 (b) 389 (c) 361
- 33.What is the smallest whole number by which 396 must be divided to get a perfect square?
- 34.What is √900? =
- 35.What is √225? =
- 36.How many whole numbers lie between 21² and 22²?
- 37.What is the smallest whole number by which 63 must be multiplied to get a perfect square?
- 38.What is the smallest whole number by which 250 must be multiplied to get a perfect square?
- 39.What is 23²? =
- 40.What is 94²? =
Answer key
- 16
- 400
- 225
- 5329
- 256
- 1600
- 2025
- 8281
- 6400
- 74
- 98
- 1296
- 31
- 625
- 84
- 784
- 169
- 289
- 7
- 64
- 7
- 72
- 39
- 3600
- 45
- 289
- 8649
- 80
- 100
- 52
- 16
- 361
- 11
- 30
- 15
- 42
- 7
- 10
- 529
- 8836
Free maths worksheets lessons, practice and worksheets at talentjr.in/maths-worksheets