How to write a system of inequalities for this story problem.?
Mark can work for at most 20 hours a week. He needs to earn at least $75 to cover his weekly expenses. His dog-walking job pays $5 dollars per hour and his car wash job pays $4 dollars and hour. Write a system of inequalities to model the situation.
- 8 years ago
I've assigned letter variables to each thing for simplicity's sake...
Work per week (W) <= 20 hrs
Total earnings (E) >= $75
Earnings for dog-walking (ED) = $5/hr
Earnings for car-washing (EC) = $4/hr
Hours worked dog-walking (HD)
Hours worked for car-washing (HC)
And most importantly, the synthesis:
HD + HC <= 20
HD(ED) + HC(EC) >= 75