A man completes ⁵/₈ of a job in 10 days. At this rate, how many more days will it takes him to finish the job?

15
26
37
4 $7 \frac{1}{2}$ $7\frac{1}{2}$

Answer:- 1

Explanation:-

Solution:

\begin{aligned} Work done = \frac{5}{8} \\ Balance work = (1 - \frac{5}{8}) = \frac{3}{8} \\ Let the required number of days be x \\ Then, \frac{5}{8} : \frac{3}{8} =:: 10 : x \Leftrightarrow \frac{5}{8} \times x = \frac{3}{8} \times 10 \\ \Rightarrow x = (\frac{3}{8} \times 10 \times \frac{8}{5}) \\ \Rightarrow x = 6 \end{aligned}

$\eqalign{ & {\text{Work}}\,{\text{done}} = \frac{5}{8} \cr & {\text{Balance}}\,{\text{work}} = \left( {1 - \frac{5}{8}} \right) = \frac{3}{8} \cr & {\text{Let}}\,{\text{the}}\,{\text{required}}\,{\text{number}}\,{\text{of}}\,{\text{days}}\,{\text{be}}\,x \cr & {\text{Then}},\,\frac{5}{8}:\frac{3}{8} = ::10:x\,\,\,\, \Leftrightarrow \,\,\,\,\frac{5}{8} \times x = \frac{3}{8} \times 10 \cr & \Rightarrow x = \left( {\frac{3}{8} \times 10 \times \frac{8}{5}} \right) \cr & \Rightarrow x = 6 \cr}$