The 6th term of an Arithmetic progression is -10 and its 10th term is -26. Determine 15th term of an Arithmetic progression

 

Asked by thakurayush007700 | 8th May, 2020, 10:39: AM

Expert Answer:

Let a and d be the first term and common difference of an AP
It is given that, 6th term a6 = -10 and 10th term a10 = -26.
Therefore,
a + 5d = -10 ... (i)
a + 9d = -26 ... (ii)
Subtracting (i) from (ii), we have
4d = -16
d = -4
Substituting in (i), we have
a + 5(-4) = -10
a = -10+20 = 10
15th term is a15 = a + 14d = 10 + 14(-4) = 10 - 56 = -46
Hence, the 15th term is -46.

Answered by Renu Varma | 8th May, 2020, 11:11: AM