Question

1.if 18,a,b,3 are in A.P then a+b=?

Answer 1

If they are in ap then
a-18 = 3- b = common difference
Therefore a+b = 18+3 = 21
Hope this helps.

Answer 2

Hiii friend,

AP = 18,a,b,3

Here,

first term (T1) = 18

Second term (T2) = a

Third term (T3) = b

And,

Four term (T4) = 3

Therefore,

Common difference (D) = T2-T1 => a-18

And,

Common difference (D) = T4-T3 = 3-b

We know that,

The common difference of an AP is always equal.

Therefore,

T2-T1 = T4-T3

=> a-18 = 3-b

=> a+b = 3+18

=> a+b = 21.


HENCE,

A+B = 21



HOPE IT WILL HELP YOU...... :-)