Answer:
a. x = 7c
b. $28
Explanation:
Her allowance starts at $20.
Out of 5 chores, for each chore she completes, she receives $3.
For each chore that she does not complete, she loses $4.
a. An expression describing her allowance
Let her total allowance be x:
x = 20 + (3 * c) + (-4 * (5 - c))
x = 20 + 3c - 20 + 4c
x = 20 - 20 + 7c
x = 7c
b. If she completes 4 chores, she will receive:
x = 7 * 4 = $28