Answer:
b. 11 apples; 1 orange
Explanation:
We test each option, and see if the total is $3.50(what you spend). If the result is different, it is not a possible solution.
a. 1 apple; 11 oranges
1 apple for $0.20
11 oranges for $0.30 each
0.20 + 11*0.30 = $3.50
Possible solution
b. 11 apples; 1 orange
11 apples for $0.20 each
1 orange for $0.30
11*0.2 + 0.3 = 2.5
Not $3.5, so this is not a possible solution.
This is the answer
c. 7 apples; 7 oranges
7*0.2 + 7*0.3 = $3.5
Possible
d. 4 apples; 9 oranges
4*0.2 + 9*0.3 = $3.5
Possible