Question

We say that a two digit number n is irie if 109 divided by n has a remainder of 4. What is the sum of all the two digit irie number

Answer 1

109–4=105.

105=3*5*7.

It is divided by

3*5=15.

3*7=21.

5*7=35.

Thus there are three 2 digit numbers(15,21,35) which divide 109 with 4 as remainder.