Answer to Question #132993 in Algebra for freya

Question

Bob finished his English assignment in 3/4 hours. Then he completed his chemistry assignment in 1/5 hours. What was the total amount of time Bob spent doing these two assignments?

Answer 1

Bob finished his English assignment in $\frac{3}{4}$ hours

Bob finished his chemistry assignment in $\frac{1}{5 }$ hours

Total amount of time he spent=Time for English Assignment+Time for Chemistry Assignment

$=\dfrac{3}{4}+\dfrac{1}{5}\\ =\cfrac{3\times5+1\times4}{4\times 5}$ ...............(On cross multiplication)

$=\cfrac{15+4}{20 }$

$=\cfrac{19}{20}hours$

Thus total time taken for Bob to complete these two assignments =$\frac{19}{20}$ hours