Question 1204278: Hi
Bob has $151.20 worth of stamps.35/100 are 10cent stamps the rest are 50 cent stamps. How many 10cent stamps does he have.
Thanks Found 2 solutions by math_tutor2020, greenestamps:Answer by math_tutor2020(3817) (Show Source):
You can put this solution on YOUR website!
T = total number of stamps
0.35T = number of 10 cent stamps
0.35T*0.10 = 0.035T = value of the 10 cent stamps only
0.65T = number of 50 cent stamps
0.65T*0.50 = 0.325T = value of the 50 cent stamps only
0.035T + 0.325T = 0.36T = total value = 151.20
0.36T = 151.20
T = 151.20/0.36
T = 420
There are 420 stamps total
35% of them are 10 cent stamps
0.35*420 = 147
There are 147 ten cent stamps
The remaining 420-147 = 273 stamps are 50 cents each.
As a check, 147*0.10 + 273*0.50 = 151.20 which helps confirm we have the right value.
Or we could have this calculation as a way to check
0.35*420*0.10 + (1-0.35)*420*0.50 = 151.20
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