If the first and fifth term’s sum is 10, then the third term of an arithmetic progression is………………
If the first and fifth term’s sum is 10, then the third term of an arithmetic progression is………………
A) 3
B) 1
C) 5
D) 2
5 views
1 Answers
Correct option is (C) 5
Given that \(a_1+a_5=10\)
\(\Rightarrow a+(a+4d)=10,\) where d is common difference \((\because a_n=a+(n-1)d)\)
\(\Rightarrow2a+4d=10\)
\(\Rightarrow a+2d=\frac{10}2=5\)
\(\therefore a_3=5\) \((\because a_3=a+2d)\)
Hence, third term of given A.P. is 5.
5 views
Answered