Answer: 1482
Step-by-step explanation:
Each number in the series is greater than the previous number by 4.
We can therefore predict that the last number is:
S + ((n-1) * 4)
where "S" is the starting number, 7 and "n" is the number of terms in the sequence, 26.
7 + (25 * 4) = 107
Add the first and the last term: 7 + 107 = 114
Add the 2nd and the 2nd to last term: 11 + 103 = 114
repeat for n/2 (13) pairs of terms. The result is 13 subtotals, each being 114.
Therefore, the solution is 13 * 114 = 1,482
