Answer:
![a_n=a_{n-1}-8;\ a_1=38](https://tex.z-dn.net/?f=a_n%3Da_%7Bn-1%7D-8%3B%5C%20a_1%3D38)
Step-by-step explanation:
The meaning of ...
![a_n=a_{n-1}-8](https://tex.z-dn.net/?f=a_n%3Da_%7Bn-1%7D-8)
is that each term is 8 less than the one before. That is the description you're trying to match.
The meaning of ...
![a_1=38](https://tex.z-dn.net/?f=a_1%3D38)
Is that the first term is 38. Even if you don't know the first term, you do know that it is not 14. The <em>fourth</em> term is 14, as the problem statement tells you. Since each term is smaller than the one before, we know the first term is larger than the fourth term, so is larger than 14.
This information is sufficient to let you choose the correct answer.
![\boxed{a_n=a_{n-1}-8;\ a_1=38}](https://tex.z-dn.net/?f=%5Cboxed%7Ba_n%3Da_%7Bn-1%7D-8%3B%5C%20a_1%3D38%7D)
To solve this, you must follow PEMDAS. First, solve the parenthesis. Because a negative times a positive equals a negative, the product of the fractions is -1/6. Then multiply that by 12. That equals -12/6. This can be simplified down to -2.
If you need more help, comment below and I will do my best.
Step-by-step explanation:
2/5 oz. for 1 cup
40 oz for x cups
2/5x = 40
x = 100 cups