Okay, thanks.
Yes, tn = a + (n – 1) d.
but i don't know how to implement it. this statement "the ratio of the 7th term to the 9th term is 5:8" is confusing me.
Homework Statement
The first term of an a.p is -8, the ratio of the 7th term to the 9th term is 5:8. what is the common difference of the progression?
Homework EquationsThe Attempt at a Solution
I've tried... it confuses me. Can anyone give me some hints or tips...?