Question

the first term of an AP is -2 and the 11th term is 18 . find its 15th term.​

Answer 1

Solution:

Let a , d are first term and common difference of an a.p

a = -2 [ given ]

11th term = a11 = 18

=> a + 10d = 18

=> -2 + 10d = 18

=> 10d = 18 + 2

=> 10d = 20

=> d = 20/10

=> d = 2

Now ,

15th term = a15

= a + 14d

= -2 + 14×2

= -2 + 28

= 26

Therefore,

15 th term = a15 = 26

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Answer 2

your answer is 26 find difference first and u will get the answer