Last week, Ellen bought 4 apples for $2.40. This week she bought 9 apples for $5.40. If the cost per apple remains the same, how many apples could she buy next week?
A.
1 apple for $1.20
B.
6 apples for $3.40
C.
10 apples for $6.00
D.
13 apples for $8.20
First, we need to calculate the cost per apple in both weeks.
For the first week, Ellen bought 4 apples for $2.40. So, the cost per apple is $2.40/4 = $0.60 per apple.
For the second week, Ellen bought 9 apples for $5.40. So, the cost per apple is $5.40/9 = $0.60 per apple.
Since the cost per apple remains the same, Ellen can buy the same amount of apples for the same amount of money in any given week.
Therefore, the answer is D. 13 apples for $8.20.