Answer:
68
Step-by-step explanation:
26 + (-84) ÷ (-2)
26 + (-84 ÷ -2)
26 + 42
68
Answer:
the answer will be
n< 80
Step-by-step explanation:
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Information Given
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Total Cost of the stamps = $9.00 - $1.75 = $7.25
Total number of stamps = 60
Value of the $0.10 stamp = $0.10
Value of the $0.15 stamp = $0.15
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Assumed all $0.10 stamps.
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Assumed all the 60 stamps she bought were $0.10 stamps.
$0.10 x 60 = $6.00
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Find amount not accounted for.
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Amount of money not accounted for:
$7.25 - $6.00 = $1.25
The $1.25 must had been used to pay for the $0.15 stamps.
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Find difference in values between the two stamps.
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Difference in the value of the two stamps:
$0.15 - $0.10 = $0.05
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Find number of $0.15 stamps
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Number of $0.15 stamps = $1.25 ÷ $0.05 = 25
There were 25 $0.15 stamps.
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Find number of $0.10 stamps.
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Number of $0.10 stamps = 60 - 25 = 35
There were 35 $0.10 stamps.
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Answer: 35 $0.10 stamps and 25 $0.10 stamps.
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I showed my answer below on paper. There are many ways to do this problem like substitution, elimination, matrices, etc... I used elimination with back-substitution. If you have any questions, let me know.
X+3y=-13
x=-3y-13
5(-3y-13) +7y = -9
-15y -65 +7y = -9
-8y-65=-9
65 -
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-74
/-8
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y= 9.25
x+3(9.25) = -13
x+27.75= -13
27.75-
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x= -40.75