5 times the 5th term of an AP is 10 times the 10th term. find the 15th term
Answers
Answered by
1
5t5=10 t10 ..... solve this
Answered by
7
Answer:
15th term is 0.
Step-by-step explanation:
5t5 = 10t10
=> 5(a + (5 - 1)d) = 10(a + (10 - 1)d)
=> 5(a + 4d) = 10(a + 9d)
=> a + 4d = 2(a + 9d)
=> a + 4d = 2a + 18d
=> a = 4d - 18d
=> a = -14d......................(1)
So, 15th term is
T15 = a +(15 - 1)d
= a + 14d
= -14d + 14d {putting the value of a in eq (1)}
= 0 (Answer).
jatinsharma2003:
thanks
Similar questions