Question

You are given the digits 5, 6, 7, 8 and 9
a, Make a 3-digit number that is in the 9 times table
b, Make a number with at least three factors, not including 1 and itself
c, Why is it impossible to make a number divisible by both 5 and 2 from those digits?
d, Is it possible to use those digits to make a 5-digit number that is divisible by 3?

Answer 1

Answer:

24

24 = 1 x 24

24 = 2 x 12

24 = 3 x 8

24 = 4 x 6

Therefore, all the factors of 24 are: 1, 2, 3, 4, 6, 8, 12 and 24.

(b) 15

15 = 1 x 15

15 = 3 x 5

Therefore, all the factors of 15 are: 1, 3, 5 and 15.

(c) 21

21 = 1 x 21

21 = 3 x 7

Therefore, all the factors of 21 are: 1, 3, 7 and 21.

(d) 27

27 = 1 x 27

27 = 3 x 9

Therefore, all the factors of 27 are: 1, 3, 9 and 27.

(e) 12

12 = 1 x 12

12 = 2 x 6

12 = 3 x 4

Therefore, all the factors of 12 are: 1, 2, 3, 4, 6 and 12.

(f) Factors of 20 are:

20 = 1 x 20

20 = 2 x 10

20 = 4 x 5

Therefore, all the factors of 20 are: 1, 2, 4, 5, 10 and 20.

(g) Factors of 18 are