Question 21991
Let x = no pounds of $7.28 coffee
7 = no pounds of $6.42 coffee
x+7 = total no pounds of coffee at $7.20

7.28x + 7*6.42 = 7.20 (x+ 7)
7.28x + 44.94 = 7.20x + 50.40
7.28x + 44.94-44.94 = 7.20x + 50.40 - 44.94
7.28x = 7.20x + 5.46
7.28x - 7.20x= 5.46
.08x = 5.46

{{{(.08x)/.08= 5.46/.08}}}
{{{x= 68.25}}} pounds at $7.28
{{{7}}} pounds at $6.42
{{{x+7= 75.25}}} pounds at $7.20


Strange--it usually comes out even, doesn't it!  But then that's life!!  It's a good idea to check it!

{{{68.25*7.28 + 7*6.42 = 75.25 *7.20 }}}
{{{496.86 + 44.94 = 541.80 }}}


R^2 at SCC