Question

find the middle term of the AP : 5 , 2 , -1 , - 4 ,......,..,- 31
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Answer 1

Answer:

-13

Step-by-step explanation:

a1 = a = 5

a2 = 2

d = a2 - a1

d = 2 - 5

d = -3

An = -31

a+(n-1)d = -31

5+(n-1)(-3) = -31

5-3n+3 = -31

-3n = -31-5-3

3n = 39

n = 13

middle term, m=(n+1)/2 = (14/2) = 7

A7 = a+(7-1)d

A7 = 5+(6*-3)

A7 = 5-18

A7 = -13