Question

Coffee café mix 90 pounds of coffee that cost six dollars per pound the types of coffee used to make this makes you cost seven dollars and four dollars per pound how many pounds of the seven dollar per pound coffee should be used in this mixture

Answer 1

y = 60

Explanation:

From the information we get:

x quantity of 4 dollars coffee used in the mix

y quantity of 7 dollars coffee used in the mix

For the quantity of coffee to be sold a 7 $/pound ( 90 pounds)

Then 6*90 = 540 $

Therefore

x + y = 90 and

4*x + 7*y = 540

A two equations system we solve for x and y

y = 90 - x

4*x + 7* ( 90 - x ) = 540

4*x + 630 - 7*x = 540

- 3*x = - 90

x = 30 pounds and

y = 90 - 30

y = 60

We should use 60 pounds of the seven $ coffee