What is the ratio of the first term of A to that of B?

Consider the following for the next three (03) items that follow : Let P be the sum of first n positive terms of an increasing arithmetic progression A. Let Q be the sum of first n positive terms of another increasing arithmetic progression B. Let P:Q=(5n+4):(9n+6)

  1. A. 1/3
  2. B. 2/5
  3. C. 3/4
  4. D. 3/5

Correct Answer: D. 3/5

Explanation

The ratio of the m-th terms of two arithmetic progressions is found by substituting n = 2m-1 into the ratio of the sums of their first n terms. To find the ratio of their first terms (m=1), we substitute n = 2(1)-1 = 1. The ratio is \frac{5(1)+4}{9(1)+6} = \frac{9}{15} = \frac{3}{5}.

Related questions on Algebra

Practice more NDA Mathematics questions