Question

If the ratio of the sum of Nth terms of two AP is 4N +2 : 3N +47 find the ratio of their ninth terms.

Answer 1

There you go!

The answer is 5:7. Hope its right.

Answer 2

         

Answer: 5 : 7

     

     

A simple method. Not explaining at all.

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$\huge\boxed{\ \ \ \ \ \huge\boxed{\ \ \ \ \ \huge\boxed{\ \ \ \ \ \bold{TO\ REMEMBER}\ \ \ \ \ }\ \ \ \ \ }\ \ \ \ \ }$

$\sf{If the ratio of the sum of} \ n\ \sf{terms of two APs is} \ (an +b) : (cn +d),\ \sf{and the ratio of their} \ m^{th}\ \sf{terms is to be found, \\ \\ take} \ n\ \sf{as} \ 2m-1.\ \sf{That's all!}$

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Here, the ratio is (4n + 2) : (3n + 47).

m = 9

So,  n = 2m - 1 = 2 × 9 - 1 = 18 - 1 = 17.

∴ (4n + 2) : (3n + 47)

⇒ (4 × 17 + 2) : (3 × 17 + 47)

⇒ (68 + 2) : (51 + 47)

⇒ 70 : 98

⇒ 5 : 7

So the ratio of 9th terms is 5 : 7.

Plz mark it as the brainliest.

Plz ask me if you have any doubt on my answer.

Thank you. :-))