A grocer wants to make a 10-pound mixture of peanuts and cashews that he can sell for $4.75 per pound. If peanuts cost $4.00 per pound and cashews cost $6.50 per pound, how many pounds of cashews should he use?

3
4
6
7

im thinking 4

Question

A grocer wants to make a 10-pound mixture of peanuts and cashews that he can sell for $4.75 per pound. If peanuts cost $4.00 per pound and cashews cost $6.50 per pound, how many pounds of cashews should he use?


3
4
6
7

im thinking 4

***[isuru]*** · Answer

nope..
 if the pounds of cashews r "x" and the pounds of peanuts r "y"
    then the 
             x + y = 10 'cause the total mixture is 10 pounds...
                      x + y = 10 -----(1)
then
 the price of pound of cashew multiply by "x" + the price of pound of peanut multiply by "y"

is equal to the price of 10 pounds of mixture
 
             (6.5)x + 4y = price of 10 pounds of mixture
but
     price of 1 pound of mixture = 4.75
so...
            (6.5)x/10 +4y/10 = 4.75
multiply the whole by 100
          65x + 40y = 475 -----(2)

now u want to find the value of "x"
          multiply (1) by 40
            40x + 40y = 400 ----(3)

(2) - (3)
         25x = 75
            x = 3

so.. the no, of pounds that he should use is 3

hope this will help ya!!