the series which satisfies the above condition is

13, 17, 21….97

To find: the sum of all two - digit numbers which when divided by 4, yields 1 as the remainder

So, it is an AP whose first term is 13 and common difference d as 4

Now for the finding number of terms, the formula is

And

n = 22

we know that the sum of AP is given by the formula:

substituting the values in the above equation

s = 1210