Divisibility Rules and Factors Worksheet
The method (Rules and powers): By 3 or 9: the digit sum divides by 3 or 9. By 4: the last two digits. By 8: the last three digits. By 6: even and divisible by 3. By 11: the sums of alternate digits are equal or differ by 11. Number of factors: write n = p^a × q^b …, then the count is (a + 1) × (b + 1) × …. To make n divisible by d: divide, then add (d − remainder) or take away the remainder.
NameDateTime takenScore ___ / 40
- 1.How many factors does 23 have?
- 2.What is the smallest number you must take away from 239 so that it divides exactly by 8?
- 3.Which of these numbers divides exactly by 6? (a) 8123 (b) 9117 (c) 3219 (d) 9396
- 4.What is the smallest number you must add to 659 so that it divides exactly by 7?
- 5.What is the smallest number you must take away from 684 so that it divides exactly by 7?
- 6.What is the smallest number you must add to 291 so that it divides exactly by 11?
- 7.How many factors does 30 have?
- 8.How many factors does 72 have?
- 9.What is the smallest number you must take away from 266 so that it divides exactly by 3?
- 10.What is the smallest number you must take away from 299 so that it divides exactly by 7?
- 11.What is the smallest number you must take away from 104 so that it divides exactly by 11?
- 12.Which of these numbers divides exactly by 11? (a) 3137 (b) 1886 (c) 4675 (d) 9706
- 13.What is the smallest number you must take away from 313 so that it divides exactly by 3?
- 14.Which of these numbers divides exactly by 4? (a) 7444 (b) 7735 (c) 5535 (d) 2898
- 15.What is the smallest number you must add to 935 so that it divides exactly by 7?
- 16.How many factors does 73 have?
- 17.What is the smallest number you must take away from 629 so that it divides exactly by 13?
- 18.What is the smallest number you must take away from 457 so that it divides exactly by 6?
- 19.How many factors does 77 have?
- 20.Which of these numbers divides exactly by 9? (a) 7785 (b) 2669 (c) 2626 (d) 4760
- 21.How many factors does 43 have?
- 22.How many factors does 97 have?
- 23.What is the smallest number you must add to 127 so that it divides exactly by 9?
- 24.What is the smallest number you must add to 428 so that it divides exactly by 8?
- 25.What is the smallest number you must take away from 660 so that it divides exactly by 8?
- 26.What is the smallest number you must add to 563 so that it divides exactly by 3?
- 27.Which of these numbers divides exactly by 11? (a) 7918 (b) 4262 (c) 1782 (d) 5623
- 28.How many factors does 17 have?
- 29.What is the smallest number you must take away from 292 so that it divides exactly by 3?
- 30.What is the smallest number you must add to 707 so that it divides exactly by 4?
- 31.How many factors does 96 have?
- 32.Which of these numbers divides exactly by 8? (a) 7958 (b) 8907 (c) 1728 (d) 9495
- 33.How many factors does 74 have?
- 34.Which of these numbers divides exactly by 9? (a) 7555 (b) 2352 (c) 4806 (d) 6024
- 35.How many factors does 38 have?
- 36.How many factors does 71 have?
- 37.Which of these numbers divides exactly by 3? (a) 4030 (b) 3620 (c) 6075 (d) 3356
- 38.How many factors does 90 have?
- 39.What is the smallest number you must take away from 997 so that it divides exactly by 11?
- 40.What is the smallest number you must take away from 168 so that it divides exactly by 13?
Answer key
- 2
- 7
- 9396
- 6
- 5
- 6
- 8
- 12
- 2
- 5
- 5
- 4675
- 1
- 7444
- 3
- 2
- 5
- 1
- 4
- 7785
- 2
- 2
- 8
- 4
- 4
- 1
- 1782
- 2
- 1
- 1
- 12
- 1728
- 4
- 4806
- 4
- 2
- 6075
- 12
- 7
- 12
Free quantitative aptitude lessons, practice and worksheets at talentjr.in/quantitative-aptitude