Question

The sum of all two digit numbers divisible by 5 is select one: a. None of these b. 1245 c. 1035 d. 945 e. 1230

Answer 1

=> Least two digit multiple of 5= 10

=> Greatest two digit multiple of 5 = 95

=> No. of numbers (by considering as AP):

$\frac{95 - 10}{5} + 1 \\ \\ \frac{85}{5} + 1 \\ \\ 17 + 1 \\ \\ 18$

=> Sum of numbers:

$\frac{18}{2}(10 + 95) \\ \\ 9 \times 105 \\ \\ \bold{945}$

=> Answer is (d) 945.