Question

5) If the second term of an AP is 13 and the fifth term is 25, what is its seventh term?.

Answer 1

Answer:

33

Step-by-step explanation:

Given, a2 = 13 and a5 = 25

⇒ a + (2-1)d = 13 [∵ an = a + (n-1)d]

and a + (5-1)d = 25

⇒ a + d = 13 ...(i)

and a + 4d = 25 ...(ii)

On subtracting Eq.(i) from (ii), we get

3d = 25 - 13 = 12 ⇒ d = 4

From Eq.(i), a = 13 - 4 = 9

∴ a7 = a + (7-1)d = 9 + 6 × 4 = 33