Question

Jumlah kelipatan 6 antara 100 sampai 300

Answer 1

A = U1 = 102
b = 6

Un = a + (n - 1) b
294 = 102 + (n - 1) 6
294 = 102 + 6n - 6
294 = 96 + 6n
294 - 96 = 6n
198 / 6 = n
n = 33

S33 = n / 2 (a + U33)
       = 33 / 2 (102 + 294)
       = 33 / 2 * 396
       = 6534