Respuesta :
This question was not written properly
Complete Question
Steve has 54 stamps in his collection of 13 cent, 29 cent, and 45 cent stamps, totaling a value of $15.98. If the number of 13 cent stamps is doubled, the new total value of his stamp collection would be $17.80. Find the number of each type of stamp in his collection.
Answer:
a) The number of 13 cent = 14
b) The number of 29 cent = 24
c) The number of 45 cent = 16
Step-by-step explanation:
We are told he has 54 stamps in total.
These stamps are;13 cent, 29 cent, and 45 cent stamps.
Let's
Number of 13 cent = a
Number of 29 cent = b
Number of 45 cent = c
Hence,
a + b + c = 54........... Equation 1
The total value of the 3 stamps are $15.98.
1 cent = $0.01
We have
0.13a + 0.29b + 0.45c= $15.98 ......... Equation 2
We know from the question that:
13 cent stamps is doubled, the new total value of his stamp collection would be $17.80.
Therefore
2(0.13a) + 0.29b + 0.45c = 17.8
0.26a + 0.29b + 0.45c = 17.8 ......... Equation 3
Combining Equation 2 and 3 together
0.13a + 0.29b + 0.45c= 15.98 ......... Equation 2
0.26a + 0.29b + 0.45c = 17.8 ......... Equation 3
We eliminate b and c by Subtracting Equation 3 from 3
0.13a = 1.82
a = 1.82/0.13
a = 14
a + b + c = 54........... Equation 1
Since a = 14
14 + b + c = 54
b + c = 54 - 14
b + c = 40
c = 40 - b
Substitute 40 - b for c and 14 for a is Equation 2
0.13a + 0.29b + 0.45c= 15.98 ......... Equation 2
0.13(14 ) + 0.29b + 0.45(40 - b) = 15.98
= 1.82 + 0.29b + 18 - 0.45b = 15.98
Collect like terms
1.82 + 18 - 15.98 = 0.45b - 0.29b
3.84 = 0.16b
b = 3.84/0.16
b = 24
Hence: Solving for c
a + b + c = 54........... Equation 1
14 + 24 + c = 54
38 + c = 54
c = 54 - 38
c = 16
Therefore,
The number of 13 cent = 14
The number of 29 cent = 24
The number of 45 cent = 16
