Question 357931: Post card stamps are $.20 each. While letter stamps cost $.33 each. If you have 50 stamps worth $12.60, how many of each type do you have?
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! Post card stamps are $.20 each. While letter stamps cost $.33 each. If you have 50 stamps worth $12.60, how many of each type do you have?
------------------
Let the number of post card stamps be "c".
The cost of c of these stamps is 20c cents.
------------------
Let the number of letter stamps be "s"
The cost of s of these stamps is 33s cents.
Equations:
Quantity Eq.::: c + s = 50 stamps
Value Eq:::::: 20c+33s = 1260 cents
------------------------------------
Set up the equations for elimination.
-----
Multiply thru the 1st equation by 20 to get:
20c + 20s = 20*50
----
Subtract that from the Value Eq. and solve for "s":
13s = 260
s = 20 (# of letter stamps)
---
Since c+s = 50, c = 30 (# of post card stamps.
==============================================
Cheers,
Stan H.
|
|
|