One of the most important and exam oriented question from Chapter name- Arithmetic Progression
Class 10th
Chapter number- 9
Exercise :- 9.4
This type of question has been asked in previous years exams.
In this question we have been given an arithmetic progression. And we have to find out which term of the AP 4. 9, 14, …. is 254.
CBSE DHANPAT RAI publication
Understanding CBSE Mathematics
Question 2 (iii)
Given A. P 4, 9, 14, …………
First term (a) = 4,
nth term is 254
Common difference (d) = a2 – a1
d = 9 – 4 = 5
As we know that, to find nth term in an A.P = a + (n – 1)d
4 + (n – 1)5 = 254
(n – 1)∙5 = 250
n – 1 = 250/5 = 50
n = 51
Hence 51th term in the A.P is 254.