Question

Pls help! The sum of the digits of a certain two-digit number is 5. When you reverse its digits you

decrease the number by 9. What is the number?

Answer 1

answer: 32

Consider 2 digit numbers whose sum is 5

5

x

0

→

5

+

0

=

5

4

x

1

→

4

+

1

=

5

3

x

2

→

3

+

2

=

5

Now reverse the digits and compare with original 2 digit number. Starting with 4 1

4

x

1

→

1

x

4

and

41

−

14

=

27

≠

9

3

x

2

→

2

x

3

and

32

−

23

=

9

⇒

the number is

32