Book Maths Puzzle

The sum of n terms of two arithematic progressions are in the ratio (3n+8):(7n+15) the ratio of 12th term are

Read Solution (Total 1)

put n=2*12-1=23

so the ratio of 12th term = (3*23+8):(7*23+15)=77:176=7:16
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Book Other Question

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