the first term of an arithmetic progression is-4 and 15th term is double the 5th term. find the 12th term.

Answer 1

search for Math is Fun arithmetic sequence
(I can not post URLs today)

Answer 2

https://www.mathsisfun.com/algebra/sequences-sums-arithmetic.html

(Damon, contact Leo.)

Answer 3

https://www.mathsisfun.com/algebra/sequences-sums-arithmetic.html
Yes! Working now, thanks :)

Answer 4

Yayyy! =)

Answer 5

Given F1= -4
So F15= F1+14d=-4+14d=2[F1+4d]=2F1+8d
-4+14d=2*-4+8d=-8+8d
14d-8d=-8+4
6d=-4 d=-4/6=-2/3
F12=F1+11d=-4+11*2/3=-4+22/3=-12+22/3=10/3=3 1/3