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if 30lbs. of rice and 30lbs. of potatoes cost $30.60 and 20lbs. of rice and 12lbs. of potatoes cost $17.04, how much will 10lbs. of rice and 50lbs. of potatoes cost?______ PLEASE HELP!!!!!

User Robert Mao
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Solve this problem using a system of equations. The easiest way for this one will be to use elimination. From the first part of the problem, you can get the equation:     30.60 = 30r + 30p     and from the second part:             17.04 = 20r + 12p   Neither r nor p can be canceled right off, so you will have to multiply. I made the p's cancel by multiplying the first equation by 2 and the second by 5. This made 60p in both of them:  61.2 = 60r + 60p    and    85.2 = 100r + 60p. Now subtract the first equation from the second to get:   24= 40r       Solve for r:   r = 0.6 so every pound of rice cost 60 cents. Now plug this into one of the original equations to solve for p: p = .42 so every pound of potatoes cost 42 cents. Now multiply the cost of rice by 10 and the cost of potatoes by 50 then add these two numbers together for your final answer. Let me know what answer you get :)
User JosieP
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