Question

A family of 2 adults and 3 children went out to dinner. The total bill was $42. Each child's dinner cost $4. How much did each adult's dinner cost?​

Answer 1

Answer: Each adult’s meal costed $15

Explanation:

This situation can be modeled by the following equation:

2a + 3c = 42, where a = the cost of an adult’s meal, and c = the cost of a child’s meal

Since we know from the problem that a child’s meal costs $4, we know c:

2a + 3(4) = 42

At this point, we can just solve the resulting equation for a:

2a + 3(4) = 42

= 2a + 12 = 42 (simplify 3(4))

= 2a = 30 (subtract 12 from both sides)

= a = 15 (divide both sides by 2)

So, the cost of each adult’s meal was $15.