Transcript 2.9 – Weighted Averages

2.9 – Weighted Averages
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
$8.40/lb
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
$8.40/lb
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
$8.40/lb + $7.28/lb
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40 + 7.28
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40 + 7.28
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40 + 7.28x
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40 + 7.28x
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x =
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x =
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x =
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x =
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x = (9 + x)
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x = (9 + x)
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x = (9 + x)7.95
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6 + 7.28x
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6 + 7.28x =
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6 + 7.28x = 71.55
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6 + 7.28x = 71.55
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6 + 7.28x = 71.55 + 7.95x
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6 + 7.28x = 71.55 + 7.95x
-75.6
-75.6
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6 + 7.28x = 71.55 + 7.95x
-75.6
-75.6
7.28x
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6 + 7.28x = 71.55 + 7.95x
-75.6
-75.6
7.28x =
Example 1
Ms. Anthony wants to create a special
blend using two coffees, one priced at
$8.40/lb. and the other at $7.28/lb. How
many pounds of the $7.28 coffee should she
mix with 9 pounds of the $8.40 coffee to sell
the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6 + 7.28x = 71.55 + 7.95x
-75.6
-75.6
7.28x = -4.05
Example 1
Ms. Anthony wants to create a special blend
using two coffees, one priced at $8.40/lb. and the
other at $7.28/lb. How many pounds of the $7.28
coffee should she mix with 9 pounds of the $8.40
coffee to sell the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6 + 7.28x = 71.55 + 7.95x
-75.6
-75.6
7.28x = -4.05 + 7.95x
Example 1
Ms. Anthony wants to create a special blend
using two coffees, one priced at $8.40/lb. and the
other at $7.28/lb. How many pounds of the $7.28
coffee should she mix with 9 pounds of the $8.40
coffee to sell the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6 + 7.28x = 71.55 + 7.95x
-75.6
-75.6
7.28x = -4.05 + 7.95x
-7.95x
-7.95x
Example 1
Ms. Anthony wants to create a special blend
using two coffees, one priced at $8.40/lb. and the
other at $7.28/lb. How many pounds of the $7.28
coffee should she mix with 9 pounds of the $8.40
coffee to sell the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6 + 7.28x = 71.55 + 7.95x
-75.6
-75.6
7.28x = -4.05 + 7.95x
-7.95x
-7.95x
-0.67x
Example 1
Ms. Anthony wants to create a special blend
using two coffees, one priced at $8.40/lb. and the
other at $7.28/lb. How many pounds of the $7.28
coffee should she mix with 9 pounds of the $8.40
coffee to sell the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6 + 7.28x = 71.55 + 7.95x
-75.6
-75.6
7.28x = -4.05 + 7.95x
-7.95x
-7.95x
-0.67x =
Example 1
Ms. Anthony wants to create a special blend
using two coffees, one priced at $8.40/lb. and the
other at $7.28/lb. How many pounds of the $7.28
coffee should she mix with 9 pounds of the $8.40
coffee to sell the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6 + 7.28x = 71.55 + 7.95x
-75.6
-75.6
7.28x = -4.05 + 7.95x
-7.95x
-7.95x
-0.67x = -4.05
Example 1
Ms. Anthony wants to create a special blend
using two coffees, one priced at $8.40/lb. and the
other at $7.28/lb. How many pounds of the $7.28
coffee should she mix with 9 pounds of the $8.40
coffee to sell the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6 + 7.28x = 71.55 + 7.95x
-75.6
-75.6
7.28x = -4.05 + 7.95x
-7.95x
-7.95x
-0.67x = -4.05
-0.67
-0.67
Example 1
Ms. Anthony wants to create a special blend
using two coffees, one priced at $8.40/lb. and the
other at $7.28/lb. How many pounds of the $7.28
coffee should she mix with 9 pounds of the $8.40
coffee to sell the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6 + 7.28x = 71.55 + 7.95x
-75.6
-75.6
7.28x = -4.05 + 7.95x
-7.95x
-7.95x
-0.67x = -4.05
-0.67
-0.67
x
Example 1
Ms. Anthony wants to create a special blend
using two coffees, one priced at $8.40/lb. and the
other at $7.28/lb. How many pounds of the $7.28
coffee should she mix with 9 pounds of the $8.40
coffee to sell the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6 + 7.28x = 71.55 + 7.95x
-75.6
-75.6
7.28x = -4.05 + 7.95x
-7.95x
-7.95x
-0.67x = -4.05
-0.67
-0.67
x=
Example 1
Ms. Anthony wants to create a special blend
using two coffees, one priced at $8.40/lb. and the
other at $7.28/lb. How many pounds of the $7.28
coffee should she mix with 9 pounds of the $8.40
coffee to sell the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6 + 7.28x = 71.55 + 7.95x
-75.6
-75.6
7.28x = -4.05 + 7.95x
-7.95x
-7.95x
-0.67x = -4.05
-0.67
-0.67
x = 6.04
Example 1
Ms. Anthony wants to create a special blend
using two coffees, one priced at $8.40/lb. and the
other at $7.28/lb. How many pounds of the $7.28
coffee should she mix with 9 pounds of the $8.40
coffee to sell the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6 + 7.28x = 71.55 + 7.95x
-75.6
-75.6
7.28x = -4.05 + 7.95x
-7.95x
-7.95x
-0.67x = -4.05
-0.67
-0.67
x = 6.04 lbs.
Example 1
Ms. Anthony wants to create a special blend
using two coffees, one priced at $8.40/lb. and the
other at $7.28/lb. How many pounds of the $7.28
coffee should she mix with 9 pounds of the $8.40
coffee to sell the mixture for $7.95/lb.?
8.40(9) + 7.28x = 7.95(9 + x)
75.6 + 7.28x = 71.55 + 7.95x
-75.6
-75.6
7.28x = -4.05 + 7.95x
-7.95x
-7.95x
-0.67x = -4.05
-0.67
-0.67
x = 6.04 lbs.