Question

What is the missing term in the following A.P.
-10,_,_,-1​

Answer 1

Answer:

-11/2

Step-by-step explanation:

let the missing term be b

and a = -10, c = -1

now according to AP

2b = a + c

2b = -10 + (-1)

2b = -10 - 1

2b = -11

b = -11/2

Answer 2

AnSwEr

Let tye missing term in given arithmetic progression be a and b

Now series look like

-10,a,b,-1

We know that

T4=-10+(4-1)d

=>-1=-10+3d

=>9=3d

=>d=3

Now term is

a=-7

and

b=-4

2nd Method

Here

d = T2-T1

=>d=a-(-10)

=>d=a+10____1)

Or

d=t4 -t3

=>d=-1-(b)

=>d=-1-b_____(2)

Fro equation (1) and (2)

=>a+10=-1-b

=>a+b=-11

U can eliminate it