If 75\% of a number is added to 75, then the result is the number itself. The number is
(a)50
(b)60
(c)300
(d)400
Answer
Answer (as printed): C
Explanation
Let the number be $x$. Then, $75 \%$ of $x+75=x \Leftrightarrow x-\frac{75}{100} x=75 \Leftrightarrow x-\frac{3}{4} x=75$ $\Leftrightarrow \frac{x}{4}=75 \Leftrightarrow x=300$.
Explanation as extracted from the printed page; notation may be imperfect.