Question

Mark the correct alternative in each of the following:

By what number should $1\frac{3}{4}$ be divided to get $2\frac{1}{2}$?

(a) $\frac{3}{7}$ (b) $1\frac{2}{5}$ (c) $\frac{7}{10}$ (d) $1\frac{3}{7}$

Answer 1

Let the required number be x.

Now,

$$\begin{gathered} 1\frac{3}{4}÷x=2\frac{1}{2} \\ \Rightarrow \frac{7}{4}\times \frac{1}{x}=\frac{5}{2} \\ \Rightarrow x=\frac{7}{4}\times \frac{2}{5} \\ \Rightarrow x=\frac{7\times 1}{2\times 5} \\ \Rightarrow x=\frac{7}{10} \end{gathered}$$

Thus, the required number is $\frac{7}{10}$.

Hence, the correct answer is option (c).