We will form the equations for this problem:
(1) 1100*y + z = 113
(2) 1500*y + z = 153
z = ? Monthly administration fee is notated with z, and that is the this problem's question.
Number of kilowatt hours of electricity used are numbers 1100 and 1500 respectively.
Cost per kilowatt hour is notated with y, but its value is not asked in this math problem, but we can calculate it anyway.
The problem becomes two equations with two unknowns, it is a system, and can be solved with method of replacement:
(1) 1100*y + z = 113
(2) 1500*y + z = 153
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(1) z = 113 - 1100*y [insert value of z (right side) into (2) equation instead of z]:
(2) 1500*y + (113 - 1100*y) = 153
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(1) z = 113 - 1100*y
(2) 1500*y + 113 - 1100*y = 153
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(1) z = 113 - 1100*y
(2) 400*y + 113 = 153
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(1) z = 113 - 1100*y
(2) 400*y = 153 - 113
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(1) z = 113 - 1100*y
(2) 400*y = 40
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(1) z = 113 - 1100*y
(2) y = 40/400
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(1) z = 113 - 1100*y
(2) y = 1/10
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if we insert the obtained value of y into (1) equation, we get the value of z:
(1) z = 113 - 1100*(1/10)
(1) z = 113 - 110
(1) z = 3 dollars is the monthly fee.
3,000 + 500 + 10 + 6 + 0.5 + 0.06 + 0.008
If we observe closely the given, we can note that the
terms given are perfect cubes. That is,
<span> x^3 is
cube of x and</span>
<span> 343 is
cube of 7</span>
Hence, the expression is the sum of two cubes. For the
sum of cubes, we follow the following rule for the factoring:
<span> a^3 + b^3 = (a +
b)(a^2 – ab + b^2)</span>
Applying the rule to the given, the factors would be:
<span> X^3 + 373 = (x +
7)(x^2 – 7x + 49)</span>
Answer: 6 cups
Step-by-step explanation:
60 cookies = 4 cups
60 + 30 = 90, and half of 60 is 30. So half of 4 cups is 2 cups.
4 cups plus 2 cups is 6 cups!
Jesse received a 25% discount.
