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 sum of the first 12 odd numbers (1 + 3 + 5 + …)?
- 2.How many whole numbers lie between 34² and 35²?
- 3.Which of these is a perfect square? (a) 704 (b) 707 (c) 676
- 4.What is the smallest whole number by which 1215 must be divided to get a perfect square?
- 5.What is the sum of the first 19 odd numbers (1 + 3 + 5 + …)?
- 6.What is 87²? =
- 7.What is the smallest whole number by which 448 must be divided to get a perfect square?
- 8.What is the smallest whole number by which 99 must be multiplied to get a perfect square?
- 9.How many whole numbers lie between 37² and 38²?
- 10.Which of these is a perfect square? (a) 1645 (b) 1643 (c) 1600
- 11.What is √1156? =
- 12.What is √9216? =
- 13.What is 62²? =
- 14.Which of these is a perfect square? (a) 1156 (b) 1167 (c) 1189
- 15.What is the smallest whole number by which 686 must be multiplied to get a perfect square?
- 16.What is √144? =
- 17.What is the sum of the first 11 odd numbers (1 + 3 + 5 + …)?
- 18.What is the smallest whole number by which 208 must be divided to get a perfect square?
- 19.Which of these is a perfect square? (a) 214 (b) 208 (c) 196
- 20.What is √729? =
- 21.Which of these is a perfect square? (a) 525 (b) 484 (c) 488
- 22.How many whole numbers lie between 15² and 16²?
- 23.What is the smallest whole number by which 360 must be multiplied to get a perfect square?
- 24.Which of these is a perfect square? (a) 798 (b) 801 (c) 784
- 25.What is 45²? =
- 26.What is 56²? =
- 27.How many whole numbers lie between 43² and 44²?
- 28.What is the smallest whole number by which 98 must be divided to get a perfect square?
- 29.What is √6241? =
- 30.What is the smallest whole number by which 50 must be multiplied to get a perfect square?
- 31.Which of these is a perfect square? (a) 138 (b) 128 (c) 121
- 32.What is 73²? =
- 33.How many whole numbers lie between 27² and 28²?
- 34.What is 65²? =
- 35.Which of these is a perfect square? (a) 320 (b) 289 (c) 299
- 36.What is the smallest whole number by which 1134 must be divided to get a perfect square?
- 37.What is the sum of the first 13 odd numbers (1 + 3 + 5 + …)?
- 38.How many whole numbers lie between 46² and 47²?
- 39.What is the sum of the first 24 odd numbers (1 + 3 + 5 + …)?
- 40.What is the sum of the first 7 odd numbers (1 + 3 + 5 + …)?
Answer key
- 144
- 68
- 676
- 15
- 361
- 7569
- 7
- 11
- 74
- 1600
- 34
- 96
- 3844
- 1156
- 14
- 12
- 121
- 13
- 196
- 27
- 484
- 30
- 10
- 784
- 2025
- 3136
- 86
- 2
- 79
- 2
- 121
- 5329
- 54
- 4225
- 289
- 14
- 169
- 92
- 576
- 49
Free maths worksheets lessons, practice and worksheets at talentjr.in/maths-worksheets