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.What is the smallest number you must take away from 478 so that it divides exactly by 7?
- 2.What is the smallest number you must add to 279 so that it divides exactly by 6?
- 3.What is the smallest number you must add to 802 so that it divides exactly by 4?
- 4.What is the smallest number you must take away from 273 so that it divides exactly by 8?
- 5.What is the smallest number you must take away from 167 so that it divides exactly by 8?
- 6.Which of these numbers divides exactly by 3? (a) 7813 (b) 1688 (c) 9463 (d) 7239
- 7.What is the smallest number you must take away from 136 so that it divides exactly by 11?
- 8.What is the smallest number you must take away from 664 so that it divides exactly by 11?
- 9.How many factors does 44 have?
- 10.How many factors does 29 have?
- 11.How many factors does 48 have?
- 12.How many factors does 31 have?
- 13.Which of these numbers divides exactly by 6? (a) 2280 (b) 1109 (c) 3399 (d) 3235
- 14.How many factors does 78 have?
- 15.What is the smallest number you must add to 643 so that it divides exactly by 9?
- 16.How many factors does 19 have?
- 17.What is the smallest number you must take away from 290 so that it divides exactly by 6?
- 18.What is the smallest number you must add to 794 so that it divides exactly by 7?
- 19.How many factors does 96 have?
- 20.What is the smallest number you must add to 383 so that it divides exactly by 4?
- 21.What is the smallest number you must add to 631 so that it divides exactly by 11?
- 22.How many factors does 80 have?
- 23.Which of these numbers divides exactly by 8? (a) 2732 (b) 1673 (c) 2872 (d) 1365
- 24.How many factors does 24 have?
- 25.What is the smallest number you must take away from 103 so that it divides exactly by 6?
- 26.What is the smallest number you must add to 580 so that it divides exactly by 3?
- 27.How many factors does 28 have?
- 28.How many factors does 42 have?
- 29.Which of these numbers divides exactly by 9? (a) 8523 (b) 2870 (c) 5111 (d) 9178
- 30.What is the smallest number you must add to 174 so that it divides exactly by 7?
- 31.What is the smallest number you must add to 189 so that it divides exactly by 6?
- 32.Which of these numbers divides exactly by 11? (a) 5489 (b) 7536 (c) 7957 (d) 9377
- 33.What is the smallest number you must add to 577 so that it divides exactly by 11?
- 34.What is the smallest number you must add to 236 so that it divides exactly by 11?
- 35.How many factors does 58 have?
- 36.Which of these numbers divides exactly by 4? (a) 4427 (b) 7195 (c) 4636 (d) 5926
- 37.How many factors does 97 have?
- 38.How many factors does 79 have?
- 39.What is the smallest number you must take away from 593 so that it divides exactly by 7?
- 40.What is the smallest number you must add to 485 so that it divides exactly by 12?
Answer key
- 2
- 3
- 2
- 1
- 7
- 7239
- 4
- 4
- 6
- 2
- 10
- 2
- 2280
- 8
- 5
- 2
- 2
- 4
- 12
- 1
- 7
- 10
- 2872
- 8
- 1
- 2
- 6
- 8
- 8523
- 1
- 3
- 5489
- 6
- 6
- 4
- 4636
- 2
- 2
- 5
- 7
Free quantitative aptitude lessons, practice and worksheets at talentjr.in/quantitative-aptitude