Algebra question

Question

Trail snax corp. mixes raisins that coat $5.00 per kg with peanuts that cost $3.80 pet kg. How many kilograms of raisins should be mixed with 10 kg of peanuts to obtain a mixture worth $4.00 per kg?

Answer 1

Mike,

 

Let

 

R = # pounds of raisins

P = # pounds of peanuts

T = # pounds of total mixture

 

Raisins are $5 / kg

Peanuts are $3.80 / kg

 

5R + 3.8(10) = 4T

and

R + 10 = T  

 

Let's substitute R+10 for T in the first equation.

5R + 3.8(10) = 4(R+10)

5R + 38 = 4R + 40

 

Solving for R

R = 2

 

We need 2 pounds of raisins.