Question

The common difference of an ap is 6 and its one term is 45. Is 2018, the sum of the 15 terms of the sequence?

Answer 1

Step-by-step explanation:

d=6

let A1= 45

now,

Sum of 15 terms is given by

S= n/2 [2a+(n-1)d]

= 15/2 [2(45)+(15-1)6]

=15/2[90+84]

=15/2 (174)

= 15*87

= 1305

therefore, 2018 is not the sum of 15 terms of this sequence