6 + 12 + 18 + 24 + …… + 612 = ?
Show answer & explanation
Correct answer: A
Explanation
Given:
Series = 6 + 12 + 18 + 24 + … + 612
According to the formula:
Sum of an AP (Arithmetic Progression) = n/2 × (First term + Last term)
First term (a) = 6
Common difference (d) = 6
Last term (l) = 612
n = (l − a)/d + 1 = (612 − 6)/6 + 1 = 606/6 + 1 = 101 + 1 = 102
Sum = n/2 × (a + l)
= 102/2 × (6 + 612)
= 51 × 618
= 31518