Question 1172688:  A grocer mixes chocolates worth 360 pesos per kilo with chocolate worth 400 pesos per 
kilo, making a mixture to sell at 372 pesos per kilo. If he mixes 50 kilos total, how many 
kilos of each kind does he use? 
 
 Found 3 solutions by  ikleyn, greenestamps, josgarithmetic: Answer by ikleyn(52900)      (Show Source): 
You can  put this solution on YOUR website! . 
You may start from this system of 2 equations in two unknowns
       x +    y = 50      kilograms    (mass equation)
    360x + 400y = 372*50  pesos.       (money equation)
You do the rest.
Or, equivalently, you may start with one single equation
    360x + 400*(50-x) = 372*50         (money equation)
and easily solve it 
    x =   = 35.
ANSWER.  35 kilo at 360 pesos per kilo and (50-35) = 15 kilo at 400 pesos per kilo.
 
Solved.
 
 
 
 
 Answer by greenestamps(13214)      (Show Source): 
You can  put this solution on YOUR website! 
  
Here is a quick and easy alternative to the standard algebraic solution method shown by the other tutor.
  
(1) The price of the mixture per kilo, 372, is 12/40 = 3/10 of the way from 360 to 400, the prices per kilo of the two kinds of chocolates.  (Look at the three numbers on a number line, if it helps....)
  
(2) That means 3/10 of the mixture is the more expensive chocolates.
  
ANSWER: 3/10 of 50 kilos = 15 kilos of the more expensive chocolates; the other 35 kilos of the less expensive.
  
CHECK: 
15(400)+35(360) = 6000+12600 = 18600 
50(372) = 18600
  
 
 Answer by josgarithmetic(39630)      (Show Source): 
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