Question

The cost of coffee is determined by the type of coffee beans that are mixed together. The cost of a local mix of Arabica and Robusta beans is modeled by the equation below where A = the pounds of Arabica and R = pounds of Robusta.

700A + 1200R = 1,000,000

If a mixture contains 1000 pounds of Arabica beans, how many pounds of Robusta beans should be in the mixture?

R = ________________ pounds

Answer 1

You might be confused because you're given one equation with two variables, and you can't directly solve that. But, then the question tells you that the mixture contains 1000 pounds of Arabica beans, so A = 1000. So:

700*1000 + 1200R = 1,000,000
1200R = 300,000
R = 250

So, that's 250 pounds of Robusta beans.

Answer 2

i think R=250
because 700*1000=700,00
then you subtract100,000,00 and 700,000
and divide that by 1200

Answer 3

srossd is correct....just sub 1000 in for A and then solve for R.