Question

An electrician charges $40 per visit, and $20 per hour of work. On a particular day, he made 3 visits and calculated that his average earnings were $50 per hour. Use this information to complete the statement. He worked hours that day.

Answer 1

4 hours

Explanation:

For three visits, the electrician earned $40 × 3 = $120 in "per-visit" charges. For working x hours, he earned 20x in "per-hour" charges. The total of these came to 50x:

120 +20x = 50x

120 = 30x . . . . . . . . subtract 20x

4 = x . . . . . . . . . . . . . divide by 30

The electrician worked 4 hours that day.