Question

Subtract the following
$3$ hours $55$ minutes from $7$ hours $15$ minutes.________

Answer 1

$3$ hours $55$ minutes $=3\times 60+55$ min $=235$ min

$7$ hours $15$ minutes $=7\times 60+15$ min $=435$ min

Subracting $3$ hours $55$ minutes from $7$ hours $15$ minutes gives $435-235=200$ min $=3\times 60+20=3$ hours $20$ min