Question

4
4
2) What is the sum of first 15 terms of the A.P. 5, 10, 15, ...?
(a) 600
(b) 65
(c) 120
(d) 225​

Answer 1

Answer:

a) 600

Step-by-step explanation:

$\frac{n}{2} (2a+(n-1)d)$

$\frac{15}{2} (2(5)+(15-1)5)\\= \frac{15}{2} (10+70)\\=\frac{15}{2} (80)\\= 600$

a) 600

Answer 2

please mark as branliest answer