Answer:
$15.44 each
Explanation:
First let's add the tip. 18% = 0.18.
52.35 x 0.18 = 9.42.
Add the tip to the total.
9.42 + 52.35 = $61.77.
The problem says that it's Mark and his 3 friends. So there are 4 people total.
Divide the total bill (including tip) by 4.
$61.77/4 = $15.44 each.