Question

Find the number which when multiplied by $17$ increases by $640$.

• A. $42$
• B. $26$
• C. $40$
• D. $45$

Answer 1

The correct option is C $40$

Let the number be $x$.

Then, $17x=x+640$

$\Rightarrow 17x-x=640$

$\Rightarrow 16x=640$

$\Rightarrow x=\frac{640}{16}=40$
Hence, required number is $40$.