Find the middle term of the AP 10, 7, 4, ………. (-62).

1.	Find the middle term of the AP 10, 7, 4, ………. (-62).
Answer» AP is 10, 7, 4, …..…, (-62) a = 10, d = 7 – 10 = -3, and l = -62 Now, a_n = l = a + (n – 1)d -62 = 10 + (n – 1) x (-3) -62 – 10 = -3(n- 1) -72 = -3(n – 1) Or n = 24 + 1 = 25 Middle term = (25 + 1)/2 th = 13th term Find the 13^th term using formula, we get a₁₃ = 10 + (13 – 1)(-3) = 10 – 36 = -26

Answer»

AP is 10, 7, 4, …..…, (-62)

a = 10,

d = 7 – 10 = -3, and

l = -62

Now, a_n = l = a + (n – 1)d

-62 = 10 + (n – 1) x (-3)

-62 – 10 = -3(n- 1)

-72 = -3(n – 1)

Or n = 24 + 1 = 25

Middle term = (25 + 1)/2 th = 13th term

Find the 13^th term using formula, we get

a₁₃ = 10 + (13 – 1)(-3)

= 10 – 36

= -26

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