Question

thought of a two-digit number. The unit digit of my number is 7 more than the tens digit cubed. What is my number

Answer 1

Given:

In a two digit number, the unit digit of my number is 7 more than the tens digit cubed.

To find:

The two digit number.

Solution:

Possible digits for ones places are 0,1,2,3,4,5,6,7,8,9.

Zero cannot be on tens places.

Possible digits for tens places are 1,2,3,4,5,6,7,8,9.

If digit on tens place is 1, then digit on ones place is

`1^3+7=1+7`

`1^3+7=8`

So, the required number is 18.

If digit on tens place is 2, then digit on ones place is

`2^3+7=8+7`

`2^3+7=15`

It cannot be possible because 15 is not a digit it is a two digit number.

Similarly, other numbers except 1 on the tens place are not possible.

Therefore, the required number is 18.