Question

The square of a term in the arithmetic sequence 2, 5, 8 , ........ is 2500. What is its position ?

• A. 20
• B. 15
• C. 17
• D. 25

Answer 1

Answer:

C. 17

$n^{th}term = a_n+b$

$=3n-1$

$(3n-1)^2=2500$

$(3n-1)^2=50^2$

$(3n-1)=50$

$3n=51$

$n=51/3=17$