• # question_answer A student multiplying a number by $\frac{3}{5}$ instead of $\frac{5}{3}$. What is percentage error in the calculation? A)  44%   B)  34%   C)  54%     D)  64%

Let the number be $x$. Then, difference in result $=\frac{5}{3}x-\frac{3}{5}x=\frac{16}{15}x$ Per cent error in result $=\frac{16x/15}{5x/3}\times 100%$ = 64%