SOLUTION: I really don't understand how to even begin this problem and I am not sure if this is even the correct category but my teacher fails to understand the meaning of please explain thi

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Question 218487: I really don't understand how to even begin this problem and I am not sure if this is even the correct category but my teacher fails to understand the meaning of please explain this problem and not just hand out the answers. the problem is "A grocer mixed nuts worth 80 cents per pound with nuts worth 50 cents per pound. How many pounds of each did he use to make a mixture of 30 pounds to sell at 75 cents per pound?"
Found 3 solutions by stanbon, checkley77, Earlsdon:
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website!
A grocer mixed nuts worth 80 cents per pound with nuts worth 50 cents per pound. How many pounds of each did he use to make a mixture of 30 pounds to sell at 75 cents per pound?
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Equation:
Quantity Equation: e + f = 30
Value equation: 80e + 50f = 75*30
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Multiply thru the Quantity Equation by 50 to get:
50e + 50f = 50*30
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Subtract that from the Value Equation and solve for "e":
30e = 25*30
e = 25 lbs. (# of lbs. of 80 cent nuts in the mixture)
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Substitute that into e+f=30 to solve for "f":
25 + f = 30
f = 5 lbs. (# of lbs. of fifty cent nuts in the mixture)
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Cheers,
Stan H.

Answer by checkley77(12844)   (Show Source):
You can put this solution on YOUR website!
.80X+.50(30-X)=.75*30
.80X+15-.50X=22.5
.30X=22.5-15
.30X=7.5
X=7.5/.3
X=25 POUNDS OF $.80 NUTS.
30-25=5 POUNDS OF $.30 NUTS.
PROOF:
.80*25+.5*5=.75*30
20+2.5=22.5
22.5=22.5

Answer by Earlsdon(6294)   (Show Source):
You can put this solution on YOUR website!
Ok, begin by assigning a variable to the unknown quantity.
Let x = the number of pounds of nuts worth 0.80 per pound, then (30-x) = the number of pounds of nuts worth $0.50 per pound. The sum of these two amounts is going to = 30 pounds of nut-mixture worth $0.75 per pound.
These can be expressed algebraically as:
Simplify and solve for x.
Combine the x-terms.
Subtract 15 from both sides.
Divide both sides by 0.3

So the grocer will need to mix 25 pounds of nuts worth $0.80 per pound with (30-25 = 5) pounds of nuts worth $0.50 per pound to obtain 30 pounds of nut-mixture worth $0.75 per pound.