Posted by Courtney on Saturday, November 13, 2010 at 11:22pm.
let the number of 20 cent stamps be x
then the number of 33 cent stamps is 50-x
solve:
20x + 33(50-x) = 1260
After solving the equation i get 3.9=x
??? isnt there a way you can solve it by letting x= number of postcard stamps and then y= number of letter stamps?
sure:
number of postcards stamps x
number of letter stamps y
x + y = 50
20x + 33y = 1260
from the first:: y = 50-x
then in the second
20x + 33(50-x) = 1260
well, look at that! I had that in the first line.
solution:
20x + 1650 - 33x = 1260
-13x = -390
x = 30
then y = 50-x = 50-30 = 20
(how did you get a decimal??? of 3.9x ? )
THANK YOU!!!!!! sorry! i feel like a waste of time for you, but im just not that smart ;)
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