Question

A store sells Brazilian coffee for $10 per lb. and Columbian coffee for $14 per lb. If the store decides to make a 150-lb. blend of the two and sell it for $11 per lb., how much of each type of coffee should be used?

Answer 1

Answer:

The store should use 112.5 pounds of Brazilian coffee and 37.5 pounds of Colombian cofee.

Step-by-step explanation:

Let "b" be the amount of Brazilian coffee, in pounds, required for the blend and "c" the amount of Colombian coffee required, in pounds.

Since there are two unknown variables a two-equation system is needed to solve the problem, we can set up one equation for weight and another for price as follows:

$b+c=150\\10*b+14*c=11*150$

Solve for "c" by multiplying the first equation by -10 and adding it to the second one:

$b+c=150\\10b+14c -10b-10c=11*150 -(10*150)\\4c=150\\c = 37.5$

Now, solve for b by replacing the value obtained into the first equation

$b+c=150\\b= 150 - 37.5\\b=112.5$

The store should use 112.5 pounds of Brazilian coffee and 37.5 pounds of Colombian cofee.