###
**The next term of the A.P., $\sqrt{7}, \sqrt{28}, \sqrt{63}, \ldots \ldots$**

A. $\sqrt{70}$
B. $\sqrt{87}$
C. $\sqrt{97}$
D. $\sqrt{112}$
**Answer: Option D**

## Show Answer

Solution(By Apex Team)

$\begin{array}{l}
\text { A.P. is } \sqrt{7}, \sqrt{28}, \sqrt{63}, \ldots \ldots \\
\Rightarrow \sqrt{7}, \sqrt{4 \times 7}, \sqrt{9 \times 7}, \ldots . \\
\Rightarrow \sqrt{7}, 2 \sqrt{7}, 3 \sqrt{7}, \ldots \ldots \\
\therefore \text { Here } a=\sqrt{7} \text { and } \\
d=2 \sqrt{7}-\sqrt{7}=\sqrt{7} \\
\therefore \text { Next term }=4 \sqrt{7} \\
=\sqrt{(16 \times 7)} \\
=\sqrt{112}
\end{array}$

## Related Questions On Progressions

### How many terms are there in 20, 25, 30 . . . . . . 140?

A. 22B. 25

C. 23

D. 24

### Find the first term of an AP whose 8th and 12th terms are respectively 39 and 59.

A. 5B. 6

C. 4

D. 3

### Find the 15th term of the sequence 20, 15, 10 . . .

A. -45B. -55

C. -50

D. 0

### The sum of the first 16 terms of an AP whose first term and third term are 5 and 15 respectively is

A. 600B. 765

C. 640

D. 680