Question 178866
The daily payroll for 100 skilled and unskilled laborers is $8320. Each 
unskilled laborer earns $64 per day. Each skilled laborer earns $112 per 
day. How many unskilled laborers are there? What is the value of the daily 
payroll for the skilled laborers.

:
let x and y be the number of skilled and unskilled workers , respectively
:
x+y=100........eq 1
112x+64y=8320..eq 2
:
rewrite eq 1 to x=100-y and plug that value into eq 2
:
112(100-y)+64y=8320
:
11200-112y+64y=8320
:
-48y=-2880
:
{{{highlight(y=60)}}}unskilled workers
:
{{{highlight(x=100-60=40)}}}skilled workers
:
payroll for skilled: 40(112)=${{{highlight(4480)}}}