Verified Answer :

To find an estimate, the bets ting to do is to round $48 up to $50.
As you've got to find 20%, just divide $50 by 5
$50/5= $10
An estimate for a 20% tip of $48 is $10
Hope this helps :)

well to find the exact amount you can multiply 48x.20 and that is your tip!

but if you want to find out the total cost  just do 1.20x48 = 57.6

Hope this helps :)