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

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?
------------------------
Equation:
Quantity Equation: e + f = 30
Value equation: 80e + 50f = 75*30
----------------------------------
Multiply thru the Quantity Equation by 50 to get:
50e + 50f = 50*30
-------------------------
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)
---------------------------
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)
=========================================================
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.
RELATED QUESTIONS
I have no idea how to do this my teacher never taught this type to us. I tried to look in (answered by ankor@dixie-net.com)
Let P be the vector space of polynomials in "t" with real coefficients. Show that the... (answered by acerX)
i have to find the quadratic function... (answered by scott8148)
I am just beginning sixth grade math team, and I am stuck on this problem in summer... (answered by Alan3354)
I need help with this problem. I am not sure if this problem falls under the category I... (answered by whisper)
Hello! I tried solving this problem and even used my notes. But it's not making sense to... (answered by ikleyn)
Factoring out Monomials THIS IS MY LAST QUESTION AND ILL PASS MY CLASS TOMMOROW PLEASE... (answered by longjonsilver)
I tried to solve this problem but I am not sure about my answer. The thing is, I solved... (answered by fractalier)
I am not sure if this is the correct category. But please help me solve this. This is... (answered by stanbon)