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 939 so that it divides exactly by 6?
- 2.What is the smallest number you must add to 973 so that it divides exactly by 9?
- 3.What is the smallest number you must take away from 307 so that it divides exactly by 13?
- 4.What is the smallest number you must add to 951 so that it divides exactly by 11?
- 5.What is the smallest number you must take away from 253 so that it divides exactly by 6?
- 6.How many factors does 77 have?
- 7.What is the smallest number you must take away from 894 so that it divides exactly by 13?
- 8.What is the smallest number you must take away from 123 so that it divides exactly by 8?
- 9.How many factors does 37 have?
- 10.What is the smallest number you must take away from 822 so that it divides exactly by 12?
- 11.How many factors does 17 have?
- 12.Which of these numbers divides exactly by 11? (a) 4370 (b) 4115 (c) 7667 (d) 1131
- 13.What is the smallest number you must take away from 666 so that it divides exactly by 11?
- 14.How many factors does 75 have?
- 15.How many factors does 100 have?
- 16.What is the smallest number you must add to 256 so that it divides exactly by 11?
- 17.What is the smallest number you must add to 465 so that it divides exactly by 4?
- 18.What is the smallest number you must add to 766 so that it divides exactly by 12?
- 19.What is the smallest number you must add to 683 so that it divides exactly by 3?
- 20.Which of these numbers divides exactly by 6? (a) 4574 (b) 7398 (c) 9645 (d) 2228
- 21.What is the smallest number you must add to 579 so that it divides exactly by 6?
- 22.What is the smallest number you must add to 622 so that it divides exactly by 6?
- 23.What is the smallest number you must add to 878 so that it divides exactly by 8?
- 24.Which of these numbers divides exactly by 8? (a) 9703 (b) 6360 (c) 2164 (d) 4530
- 25.How many factors does 30 have?
- 26.What is the smallest number you must add to 174 so that it divides exactly by 4?
- 27.What is the smallest number you must add to 197 so that it divides exactly by 7?
- 28.How many factors does 31 have?
- 29.What is the smallest number you must take away from 985 so that it divides exactly by 13?
- 30.How many factors does 73 have?
- 31.What is the smallest number you must take away from 245 so that it divides exactly by 9?
- 32.Which of these numbers divides exactly by 11? (a) 3821 (b) 7170 (c) 2492 (d) 2805
- 33.What is the smallest number you must add to 576 so that it divides exactly by 13?
- 34.How many factors does 95 have?
- 35.What is the smallest number you must add to 211 so that it divides exactly by 8?
- 36.How many factors does 55 have?
- 37.What is the smallest number you must add to 275 so that it divides exactly by 4?
- 38.Which of these numbers divides exactly by 4? (a) 1124 (b) 3746 (c) 6037 (d) 4853
- 39.How many factors does 70 have?
- 40.What is the smallest number you must add to 193 so that it divides exactly by 12?
Answer key
- 3
- 8
- 8
- 6
- 1
- 4
- 10
- 3
- 2
- 6
- 2
- 7667
- 6
- 6
- 9
- 8
- 3
- 2
- 1
- 7398
- 3
- 2
- 2
- 6360
- 8
- 2
- 6
- 2
- 10
- 2
- 2
- 2805
- 9
- 4
- 5
- 4
- 1
- 1124
- 8
- 11
Free quantitative aptitude lessons, practice and worksheets at talentjr.in/quantitative-aptitude