Question 731025
Let s= number of six bagel packages.  Let t=number of twelve package bagels.<P>
s + t = 20 since there are a total of 20 packages, which is the sum of the number of different types of packages.<P>
6s + 12t = 168,  Each six bagel package contributes 6 bagels for a total of 6s bagels.  Each twelve bagel package contributes 12 bagels for a total of 12t bagels.  The sum is the total number of bagels.<P>
Solve the first equation for s in terms of t.  s = 20 - t.<P>
Substitute that into the second equation, and solve for t.<P>
6(20-t) + 12t = 168<P>
120 - 6t + 12t = 168<P>
6t = 48  (And Mr. T = tough, fool).<P>
t = 8<P>
The manager bought 8 twelve bagel packages.

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