Volume of cone = (1/3)pi*r²h
56.52 = (1/3)*3.14*r²*6
56.52/(2*3.14) = r²
9 = r²
r² = 9
r = √9
r = 3
Diameter = 2*r = 2*3 = 6 inches. b.
Answer: y = 6 mi. .
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Explanation:
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Area of a triangle = (½) * (base) * (height) ;
or, A = (½) * b * h ; or, A = b*h / 2 ;
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Given: A = 24.3 mi ² ;
b = 8.1 mi
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Find the height, "h" ; (in units of "miles", or , "mi" ).
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Plug in the known values into the formula:
24.3 mi ² = (½) * (8.1 mi) *(h) ;
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Solve for "h" (height) ;
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(½) * (8.1 mi) = 4.05 mi ;
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Rewrite:
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24.3 mi² = (4.05 mi) *(h) ; Solve for "h" ;
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Divide each side of the equation by "(4.05 mi)" ; to isolate "h" on one side of the equation ; and to solve for "h" ;
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24.3 mi² / 4.05 mi = (4.05 mi) *(h) / 4.05 mi ;
→ 6 mi = h ; ↔ h = 6 mi.
→ h = y = 6 mi.
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Answer: the cost per unit of gas is $0.38
Step-by-step explanation:
Let x represent the cost per unit of electricity.
Let y represent the cost per unit of gas.
During one month, a homeowner used 600 units of electricity and 100 units of gas for a total cost of $344. It means that
600x + 100y = 344- - - - - - - - - -1
The next month, 400 units of electricity and 250 units of gas were used for a total cost of $299.
It means that
400x + 250y = 299- - - - - - - - - -1
Multiplying equation 1 by 400 and equation 2 by 600, it becomes
240000x + 40000y = 137600
240000x + 150000y = 179400
Subtracting, it becomes
- 110000y = - 41800
y = - 41800/- 110000
y = 0.38
Substituting y = 0.38 into equation 1, it becomes
600x + 100 × 0.38 = 344
600x + 38 = 344
600x = 344 - 38 = 306
x = 306/600
x = 0.51