An A.P. and a G.P. of positive terms have the same first term and the sum of their first, second and third terms are respectively, `1, 1/2` and 2. Show that the sum of their fourth terms is `19/2`

If the first second and third term of AP are a,b and 2 a respectively.Then the sum of the AP is

Find the sum of first 51 terms of the A.P. whose second and third terms are 14 and 18 respectively.

Find the sum of first 51 terms of an A.P whose second and third terms are 14 and 18 respectively.

Find the sum of first 51 terms of an A.P. whose second and third terms are 14 and 18 respectively.

In an A.P, the first term is 1 and sum of the first p terms is 0, then sum of the first (p + q) terms is

A geometrical progression of positive terms and an arithmetical progression have the same first term. The sum of their first terms is 1 , the sum of their second terms is (1)/(2) and the sum of their third terms is 2. Calculate the sum of their fourth terms.

If the second term and the fourth terms of an A.P. are 12 and 20 respectively, then find the sum of first 25 terms:

If the second term and the fourth terms of an A.P. are 12 and 20 respectively, then find the sum of first 25 terms: