Problem Solving

BlueDragon2010 wrote:A factory that employs 1,000 assembly-line workers pays each of these workers $5 per hour for the first 40 hours worked during a week and 1.5 times that rate for hours worked in excess of 40. What was the total payroll for the assembly-line workers for a week in which 30 percent of them worked 20 hours, 50 percent worked 40 hours and the rest worked 50 hours?

A) $180,000
B) $185,000
C) $190,000
D) $200,000
E) $205,000

WEEKLY SALARIES
Worker who worked 20 hours: Salary = (20)(5) = $100
Worker who worked 40 hours: Salary = (40)(5) = $200
Worker who worked 50 hours: Salary = (40)(5) + (10)(7.5) = $275

30 percent of them worked 20 hours,...
So, 300 workers worked 20 hours.
TOTAL salary for them = (300)($100) = $30,000

50 percent worked 40 hours....
So, 500 workers worked 40 hours.
TOTAL salary for them = (500)($200) = $100,000

... the rest worked 50 hours
There are 200 employees remaining.
TOTAL salary for them = (200)($275) = $55,000

TOTAL PAYROLL = $30,000 + $100,000 + $55,000 = [spoiler]$185,000 = B[/spoiler]

Cheers,
Brent