Answer:
c
Step-by-step explanation:
Answer is A. first choice
Aver. 14 - 17 years old = 75/11 = 6.8
Aver. 10 - 13 years old = 47/11 = 4.27
First create a ratio:
The sandwich cost 3.5 more than the drink therefore the ratio is 3.5:1
Then add the two sides of the ratio together to get the total parts of the ratio
3.5+1 = 4.5
Now that we know the total parts of the ratio we can solve for one part by dividing the total cost $9.90 by the total parts of the ratio 4.5+
$9.90/4.5 = 2.20
Since we know that each part of the ratio is 2.20 we multiply both sides of the ratio by 2.20
3.5 *2.20 = 7.70
1 * 2.20 = 2.20
Therefore the answer is B