Question

$\text{If the total working hours are}\frac{22}{7}\text{hours,}$
then calculate the number of hours spent in assembling.

• A. $\frac{5}{7}hrs$
  
• B. $\frac{2}{7}hrs$
• C. $\frac{3}{7}hrs$
• D. $\frac{4}{7}hrs$
  

Answer 1

The correct option is A $\frac{5}{7}hrs$


First of all, let's convert the mixed fraction to improper fraction with denominator 7.

$1\frac{2}{7}$ $\text{= 1 +}\frac{2}{7}\text{=}\frac{7}{7}\text{+}\frac{2}{7}\text{=}\frac{9}{7}$

$\text{Time taken in stamping =}\frac{4}{7}hrs$

$\text{Time taken in welding =}\frac{1}{7}hrs$

$\text{Time taken in painting =}\frac{9}{7}hrs$

$\text{Time taken in inspection =}\frac{3}{7}hrs$

$\text{Total time taken =}\frac{22}{7}hrs$

$\text{Time taken in assembling will be:}$
$\Rightarrow \frac{22}{7}-\frac{4+1+9+3}{7}$

$\Rightarrow \frac{22}{7}-\frac{17}{7}$

$\Rightarrow \frac{22-17}{7}$

$\Rightarrow \frac{5}{7}hrs$

$\text{Hence,}\frac{5}{7}\text{hours are taken in assembling.}$

$\text{Marking the points on a line plot:}$