Question

Subtract $12hr$ $58min$ from $20hr$ $5min$.

Answer 1

Hint: Convert $20hr$ $5min$ in such a way that it is easier to subtract the other entity with it.

Complete step-by-step answer:
$20hr + 5\min = 19hr + 1hr + 5\min $
We can write $1hr$ as $60mins$,
Therefore,on adding the minutes, we get,
$20hr + 5mins$ = $19hr + 65mins$
Now, we can perform the subtraction,
$19hr$ $65mins$ - $12hrs$ $58min$
$Answer$ = $7hrs$ $7mins$

Note: You can also convert the minutes to hours, but it will involve fraction, so it is better if we convert the hour to minutes.