SOLUTION: problem- If 20 lbs of rice and 10 lbs of potatoes cost $16.20, and 30 lbs of rice and 12 lbs of potatoes cost $23.04, how much will 10 lbs of rice and 50 lbs of potatoes cost?
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-> SOLUTION: problem- If 20 lbs of rice and 10 lbs of potatoes cost $16.20, and 30 lbs of rice and 12 lbs of potatoes cost $23.04, how much will 10 lbs of rice and 50 lbs of potatoes cost?
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Question 150947: problem- If 20 lbs of rice and 10 lbs of potatoes cost $16.20, and 30 lbs of rice and 12 lbs of potatoes cost $23.04, how much will 10 lbs of rice and 50 lbs of potatoes cost?
solve the linear system using the echelon method Answer by checkley77(12844) (Show Source):
You can put this solution on YOUR website! 20R+10P=16.20 MULTIPLY THIS EQUATION BY -1.5 & ADD.
30R+12P=23.04
-30R-15P=-24.30
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-3P=-1.26
P=-1.26/-3
P=.42 PRICE OF A LB. OF POTATOES.
20R+10*.42=16.20
20R+4.20=16.20
20R=16.20-4.20
20R=12
R=12/20
R=.60 PRICE OF A LB. OF RICE.
PROOF:
30*.60+12*.42=23.04
18+5.04=23.04
23.04=23.04
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