Question

If four numbers are to be inserted between the numbers 4 and 49 such that an AP is formed, then the biggest of these four numbers is

• A. 30
• B. 35
• C. 40
• D. 45

Answer 1

The correct option is C 40

Let the terms of AP be $a,a+d,a+2d,a+3d,a+4d,a+5d$.

Where $a=4$

And, $a+5d=49$

Solving these equations, we get,

$5d=45\Rightarrow d=9$

Therefore 4 inserted terms are $a+d,a+2d,a+3d,a+4d$ i.e.,

$13,22,31,40$.

Here, 40 is the biggest number.