Question

Calculate the following sums !! Look at picture. Please show how I am confused.

Answer 1

first sum is 27 second sum is 6

Answer 2

The 'crab' means the 'sum of'
so the first one means the value of sum of 3 added together 20 - 3 = 17 times.

That is 3*17 = 51

The second one is the sum of the values of n^2 -2 when n = 1,2,3,4 and 5

= 1^2 - 2 + 2^2 - 2 + ....... + 5^2- 2
= 1 + 4 + 9 + 16 + 25 - 10
= 45