Respuesta :

Answer:


Step-by-step explanation:

The total tip left by the boys amounted to 15% of the pre-tip bill.  Let p represent the pre-tip bill.

Then 0.15p = $10.50 (p is the pre-tip bill and 0.15 represents 15% of that)

Dividing both sides by 0.15 results in an expression for p:

p = $10.50 / 0.15 = $70.

Recall that p is the sum of the costs of the individual meals.  If this total was $70 and Michael's dinner cost $40, Elijah's dinner must have cost

$70 - $40, or $30.