Question

the ratio of 7th and 3rd term of an ap is 12 :15 find the ratio of 13 and 4 term​

Answer 1

Answer:

10:3

Step-by-step explanation:

Formula of n th term in AP = a+(n-1)d

Where a is the first term

n is the term number

d is the common ratio

Now when n = 7

So,a+(7-1)d=a+6d

When n = 3

So,  a+(3-1)d=a+2d

Since we are given that the ratio of 7th to 3rd term of an AP is 12:5

⇒

⇒5a+30d=12a+24d

⇒6d = 7a

⇒a=6d/7

Now 13th term =a+(13-1)d =a+12d =

4th term =a+(4-1)d =a+3d =

Now ratio of 13th and 4th term

Thus the ratio of the 13th and 4th term is 10:3

FROM====MIYABHAI007.