Question

cost of digging a well for the first metre is 200 Rs and ris's by Rs. 30 for each metre, which statement is true for this

(a) It is A.P will a= 170, d=30 (b) It is not A.P.

(C) It is AP with a = 200, d=30p (d) None of these​

Answer 1

Answer:

n/2(300+(n-1)50)

or n(125+25n)

Step-by-step explanation:

a=150 d=50 N=n

Sn=n/2(2a+(n-1)d)

Sn=n/2(300+(n-1)50)

Sn=n(125+25n)