



 
Hi Mick. Start by assigning variables to the unknowns:
Then translate the question into equation terms:
Now we can solve for B using the first equations:
And then substitute for b and B in the total cost equation:
which still leaves two variables unresolved. However, we know that W is a whole positive number (we are interpreting the word "some" in the question to mean "at least one") and w is a whole positive number as well. We also know that W is at most 16 (there must be at least one brown envelope to qualify as "some") and at least 1. So let's write this as an inequality:
substituting for W, we have
however, we know w is an integer number of cents, so
Finally, we can use this to find W and B:
Always remember to check at the end:
Hope this helps,  


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