Answer:
12 hr. mowing lawns
28 hr. working at Mc Donalds
Step-by-step explanation:
Let t = time mowing lawns
then 40 - t = time working at McDonalds
7,5(40 - t) + 6t = 282
300 - 7.5t + 6t = 282
-1.5t = -18
t = 12 hr. mowing lawns
40 - t = 40 - 12 = 28 hr. working at Mc Donalds