Question

The middle most term (s) of the AP:–11, –7, –3, ..., 49 is:

Answer 1

Answer:

Here, a = -11

d = 4

a↓n = 49

Now, a↓n = a + (n-1) d

or, 49 = -11+(n-1) 4

or, (n-1) 4 = 60

or, n = 16

Middle most term = (8th + 9th terms)/2

Now, a↓8 = a+7d = -11+28 = 17

a↓9 = a+8d = -11+32 = 21

Middle term = (17+21)/2 = 19