Rosyth Sch 2007 PSLE Math Prelim Q41

The table below shows the rates at which a construction worker is being paid daily.

How many hours must he work in a day to earn $140?

Solution

First 8 hours of work ----- $10 x 8 = $80

To earn $140, he needs another $60.

Overtime rate is ----- $10 per hour x 1.5 = $15 per hour.

For overtime pay to be equal to $60, he must work
$60 divided by $15 per hour = 4 hours

Total time he needs to work
8h + 4h = 12h

Answer: 12 hours