Answer:
406 I believe is the answer
Step-by-step explanation:
14 times 5 = 70 and add that to 21 times 16 and you get the answer
Finding the inverse function:
We are given a function y = f(x). To find the inverse function, we exchange x with y in the original function, and then isolate y.
So
We are given the function:

So

Changing x with y

Now, we have to isolate y. So

We can apply the fifth root to both sides. So:
![\sqrt[5]{(y+7)^5}=\sqrt[5]{x}](https://tex.z-dn.net/?f=%5Csqrt%5B5%5D%7B%28y%2B7%29%5E5%7D%3D%5Csqrt%5B5%5D%7Bx%7D)
![y+7=\sqrt[5]{x}](https://tex.z-dn.net/?f=y%2B7%3D%5Csqrt%5B5%5D%7Bx%7D)
Since Sylvanite only contains 28% gold by mass, then to obtain 81.0 grams of gold, x amounts of sylvanite must be mined. To determine x, we divide 81 grams by 28%. This equation is shown below:
0.28X = 81
X = 81/0.28
X = 289.29 grams
Therefore, 289.29 grams of sylvanite must be dug up to obtain 81 grams of gold.
Yes-because from the 7th term you can either go backwards or forwards to find the number/pattern/letter you need to get to