how do i solve this problem

Question

A business shipped 140 packages one day. Customers are charged $2.50
$
2.50
for each standard-delivery package and $6.50
$
6.50
for each express-delivery package. Total shipping charges for the day were $550.00
$
550.00
. How many of each kind of package were shipped?

Answer 1

Hi Michelle,

 

Let n be the number of packages sent by standard delivery. Then, there are 140 - n packages sent via express. Then we get the following equation

 

$2.50n + 6.50(140 - n) = 550.00

 

Let's first multiply both sides of this equation by 100 to get rid of the decimals.

 

250n + 650(140 - n) = 55000

 

250n + 91,000 - 650n = 55000

 

-400n = -36000

 

n = 90

 

So, 90 packages were sent standard and 140 - 90 = 50 packages were sent express.