13. 12 3/8
14. 9 2/3
15. 3 4/10
16. 3
25 × 4 = 100 - the number of all candies
2/5 of 100 is

The third model is shaded to show the total number of caramel candies in 4 bags.
Answer:
156.5
Step-by-step explanation:
Thinking process:
The area can be calculated using the formula:

We let the substitution take place.
Therefore, we let 
Thus, 
So,

Also, the interval of the integration changes to [ 37, 65]
Thus,

= 
= 156.5 units²