This is not a full question. If you were given the amount at the begining of 1970 (we'll call it x) and the amount at the end of 1980 (we'll call it y), we should solve them accordingly:
y-x=? (calling the answer a)
a/y=%(not answer yet, call this b)
b+100=answer
You need 92 muffins in total then you dived by 6 = 16
Answer:
The expression that belongs in the box is 8 x 4
Option C is correct answer.
Step-by-step explanation:
We need to find Which expression belongs in the box?

The property applied here is associative property of multiplication.
Associative property of multiplication states that:

So, if we apply the property to our question we have:
a = 3
b = 8
c = 4
So, the expression will become: 
So, the expression that belongs in the box is 8 x 4
Option C is correct answer.
Answer: x=14.4
Step-by-step explanation:
The triangle shown in the figure attache is a right triangle. Therefore, you can calculate the missing side "x" as following:

Where:

When you solve for x and substitute the values shown above, you obtain the following result:

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