Answer:
3a + 2r + 7b = 21
2a + 6r + b = 29
a + 4r + 5b = 23
Explanation:
a = price of apples
r = price of oranges (I used r instead of letter o since o can be confused with zero)
b = price of bananas
Sally went to the grocery store and bought 3 lbs. of apples, 2 lbs. of oranges, and 7 lbs. of bananas for $21.
3a + 2r + 7b = 21
Kevin bought 2 lbs. of apples, 6 lbs. of oranges and 1 lb. of bananas for $29.
2a + 6r + b = 29
Heather bought 1 lb. of apples, 4 lbs. of oranges and 5 lbs. of bananas for $23.
a + 4r + 5b = 23
The system of equations is:
3a + 2r + 7b = 21
2a + 6r + b = 29
a + 4r + 5b = 23