math question?

Question

if the cost of peanuts is 2 dollars per pound and the cost of raisins is 3.50 dollars per pound how many pounds of peanuts and how many pounds of raisins should be used to make a 3 pound blend that costs 3 dollars per pound

Answer 1

This is set up just like the buttermilk question that you asked earlier.

p is the amount of peanuts
r is the amount of raisins

p + r = 3 pounds

2p + 3.5r = 3(3)

Now solve using substitution or elimination.

Hope this helps. Next time try setting it up and asking us if you have the equations set up correctly. :)

Answer 2

This is a system of equations to solve.
p = pounds of peanuts
r = pounds of raisins

2p + 3.5r = 3*3
p + r = 3 ---> p = 3 - r

Substitute into first equation

2*(3 - r) + 3.5r = 9
6 - 2r + 3.5r = 9 ---> solve for r

1.5r = 3
r = 2

Substitute back into second equation
p = 1

Answer 3

3 pounds at $3/ pound is $9

Let p= pounds of peanuts
Let r = pounds of raisins

p + r = 3
p = 3 - r

$2.00p + $3.50r = $9.00
$2.00(3-r) + $3.50r = $9.00
$6.00 - $2.00r + $3.50r = $9.00
$1.50r = $3.00
r = 2

p = 3 - r = 3 - 2 = 1

Check
$2.00(1) + $3.50(2) = $9.00
$2.00 + $7.00r = $9.00
Correct

Answer 4

let the peanutsbe 'x' pounds and raaisins 'y' pounds
2x+3.5y=3*3
4x+7y=18
x+y=3
4x+4y=12
subtracting
3y=6
y=2
she mixes 1poundspeanuts
and2 pound raisin

Answer 5

p*2 + r*3.5=3 ----------(1)
r+p=1 --------------------(2)

(1) - 2*(2) => 3.5r - 2r = 3 - 2 => 1.5r = 1 =>r=2/3 and p= 1/3

in 1lb mix we have 1/3lb peanuts and 2/3lb raisins
in 3lb mix we get 1lb peanuts and 2lb raisins