Question 732757
Shereda bought several dozen roses and several dozen carnations. 
The roses cost $15 per dozen, and the carnations cost $8 per dozen. 
Shereda bought a total of 17 dozen flowers and paid a total of $192. How many roses did she buy?
Equations:
Quantity Eq: r + c = 17 dozen
Value Eq:::15r+ 8c = 192 dollars
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Modify:
8r + 8c = 8*17
15r+ 8c = 192
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Subtract and solve for "r":
7r = 56
r = 8 (# of dozen of roses bought)
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Solve for "c":
r + c = 17
8 + c = 17
c = 9 (# of dozen of carnations bought)
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cheers,
Stan H.
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