Solution:
If Luke gets paid $16 per hour to work at the grocery store and $22 per hour to work at the nursery, then if he works 5 hours at the grocery store and 8 hours at the nursery he gets:
earnings at the grocery store + earnings at the nursery =
($16 x 5) + ($22 x 8) = $80 + $176 = $256.
Then the correct answer is: if he works 5 hours at the grocery store and 8 hours at the nursery he gets $256.
Following this order of ideas, we can say that if he works g hours at the grocery store and n hours at the nursery then he gets:
earnings at the grocery store + earnings at the nursery =
($16 x g) + ($22 x n) = $(16g + 22n)
Then the correct answer is: if he works g hours at the grocery store and n hours at the nursery he gets $(16g + 22n)