Question

Three boxes weigh $18\frac{3}{4}\mathrm{kg},7\frac{1}{2}\mathrm{kg}\mathrm{and}10\frac{1}{5}\mathrm{kg}$ respectively. A porter carries all the three boxes. What is the total weight carried by the porter?

Answer 1

Since the porter carries all the three boxes, then total weight

$$\begin{gathered} =18\frac{3}{4}+7\frac{1}{2}+10\frac{1}{5} \\ =\frac{75}{4}+\frac{15}{2}+\frac{51}{5} \\ =\frac{75\times 5}{4\times 5}+\frac{15\times 10}{2\times 10}+\frac{51\times 4}{5\times 4} \\ =\frac{375}{20}+\frac{150}{20}+\frac{204}{20} \\ =\frac{375+150+204}{20} \\ =\frac{729}{20} \\ =36\frac{9}{20} \end{gathered}$$

Hence, the total weight carried by the porter is $36\frac{9}{20}$ kg.