Question

Christie has a total of 15 pieces of fruit, all bananas and apples, worth $1.59. Bananas are 13 cents each and apples are 7 cents each. How many bananas and how many apples does she have?

Select one:
a. 6 bananas, 9 apples
b. 9 bananas, 6 apples
c. 9 bananas, 24 apples
d. 21 bananas, 6 apples

Answer 1

Let 'a' be the amount of apples and 'b' the amount of bananas

a + b = 15 (she has 15 pieces of fruit total)
0.07a + 0.13b = 1.59 (the fruit cost $1.59 total)

The first equation can be written
b = 15 - a.
Now substitute that into the second equation.

0.07a + 0.13(15 - a) = 1.59
0.07a + 1.95 - 0.13a = 1.59
-0.06a + 1.95 = 1.59
-0.06a = -.36
a = -0.36 / -0.06
a = 6

Now plugging that back into the first equation:
b = 15 - 6 = 9.

so apples= 6
bananas = 9