Percentage - Two numbers relation question.

Question

When 40% of a number A is added to another number B, B becomes 125% of is previous value. Then which of the following is true regarding the values of A and B? (a) A > B (b) B > A (c) B =A (d) Either (a) or (b) can be true depending upon the values of A and B.

Answer 1

For such a question, it is useful to write down what we have in a mathematical way: \begin{equation} 0.4A + B = 1.25B \end{equation} Now, by subtracting $B$ on both sides, \begin{equation} 0.4A = 0.25B \end{equation} Now, as $B = 1.6A$, it must be clear what the answer should be