Question 23735
If there are 100 stamps, then let x = number of one type of stamp (either one will do!!):
Let x = number of 5 cent stamps 
100-x = number of 2 cent stamps


.05x = value of the 5 cent stamps
.02(100-x) = value of the 2 cent stamps


The value of the stamps is $3.00, so
.05x + .02(100-x) = 3.00
.05x + 2.00 - .02x = 3.00
.03x + 2.00 = 3.00


Subtract 2.00 from each side:

.03x + 2.00 -2.00= 3.00-2.00
.03x = 1.00


Divide both sides by .03:
.03x = 1.00
{{{(.03x)/.03 = 1.00/.03}}}
{{{x = 100/3 }}}
x= 33 1/3 stamps


This is NOT possible, since the answer did not come out even.  You can't have one third of a stamp.


R^2 at SCC