Question

If 20, x+1, 4 are in AP then value of x is.a)11 b)12 c)24 d) 13​

Answer 1

Answer:

(a) 11

Step-by-step explanation:

We know , when a,b,c are in AP Then there Arithmetic Mean will be

2b = (a + c)

Here , a = 20 , b = (x + 1) & c = 4

Therefore, Arithmetic Mean is :-

2(x+1) = 20+4

=> (x+1) =24/2

=> x = 12 - 1

=> x = 11