CLASS-10 MATH’S EXERCISE 5.2 Q-4

CHAPTER-5 ARITHMETIC PROGESSIONS

QUESTION -4

Which term of the A.P. 3, 8, 13, 18, … is 78?

ANSWER:

3, 8, 13, 18, …
For this A.P.,
a = 3
d = a2 − a1 = 8 − 3 = 5

Let nth term of this A.P. be 78.

Hence, 16th term of this A.P. is 78.