180 = 3x + 5x + 2x +5
180 = 10x + 5
175 = 10x
x = 17.5
180 is how many degrees in a triangle
The answer is 5 gallons
Its very simple.
Turn 60% and 10% into decimals ( .60 and .10)
Multiply 8 gallons ( brand A ) by .60 and you get 4.8 gallons
Multiply 2 gallons ( brand B ) by .10 and you get .2 gallons
Add them up and you get 5 gallons.
Any number from -10 to -∞ would be correct. One example is -79.
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.
Answer:
4/5
Step-by-step explanation:
<u>4/5 = 80%</u>
1/4 = 25%
3/10 = 30%
