The sum of the first 12 numbers of the series: 2, 6, 10, 14, ______?
The sum of the first 12 numbers of the series: 2, 6, 10, 14, ______?
Explanation
This is an arithmetic series:
2, 6, 10, 14, ...
First term (a) = 2
Common difference (d) = 6 - 2 = 4
Number of terms (n) = 12
Sum of n terms of an arithmetic series:
S = n/2 × [2a + (n - 1)d]
S = 12/2 × [2×2 + (12 - 1)×4]
S = 6 × [4 + 44] = 6 × 48 = 288