Answer:
Step-by-step explanation:
Correct
Answer:
SA = 1,176 ft².
Step-by-step explanation:
To find the surface area of the triangular prism, we can solve for the rectangular base, both triangular faces, and lateral sides separately.
For the rectangular base: (Use formula l×w)
20 × 18 = 360 ft²
For the triangular faces: (Use formula 1/2(b·h)
1/2(18 × 12) = 108 ft²
Since there are two faces, we need to double the amount.
108 × 2 = 216 ft².
Finally, solve for the lateral sides:
20 × 15 = 300 ft².
There are two sides, so:
300 × 2 = 600 ft².
Add up all of these areas:
600 + 216 + 360 = 1,176 ft²
You subtract 38.75 from 46.5, which is 7.75. 7.75/46.5=about .16666, or 16.7 percent.
To write 8/33 as a decimal you have to divide numerator by the denominator of the fraction.
<span>We divide now 8 by 33 what we write down as 8/33 and we get 0.24242424242424 </span>
<span>And finally we have: </span>
8/33 as a decimal<span> equals </span><span>0.24242424242424</span>
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.
