Problema Solution

A merchant has coffee worth $40 a pound that she wishes to mix with 80 pounds of coffee worth $70 a pound to get a mixture that can be sold for $60 a pound. How many pounds of the $40 coffee should be used?

Answer provided by our tutors

Let weight of $40 coffee = x

We have

x*40 + 80*70 = 60 *(80 + x)

=> 40x + 5600 = 4800 + 60x => 20x = 800 => x = 40 pounds