All you have to do is divide 321 by 3 to get $107.00 each night

Multiplication by 10ⁿ → move decimal n places to the right.
Multiplication by 10⁻ⁿ → move decimal n places to the left.
For n ∈ N
Since the problem stated that 7/9 of the participants were from Wisconsin, so 2/9 of it were not from Wisconsin. Now out of 7/9 participants, 3/5 of them were 12 years old, so 2/5 of them are not 12 years old. Since we now know the fractions, we'll get the equation 7/9 x 3/5 multiply 7 and 3 then divide it to the product of 9 and 5 to have the answer of 7/15. 7/15 of the participants of the camp in Green Bay is from Wisconsin and are 12 years old.