Exact Surface Area = 378pi
Approximate Surface Area = 1186.92
The approximate surface area uses pi = 3.14
The units are cm^2 or "square cm".
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Work Shown:
SA = surface area of cylinder
SA = 2*pi*r^2 + 2*pi*r*h
SA = 2*pi*7^2 + 2*pi*7*20
SA = 2*pi*49 + 2*pi*140
SA = 2*49*pi + 2*140*pi
SA = 98pi + 280pi
SA = 378pi ..... exact surface area
SA = 378*3.14
SA = 1186.92 ..... approximate surface area
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Side note: The diameter 14 cuts in half to get the radius r = 7
Answer:
A (50)
Step-by-step explanation:
Mean is the total numbers added up divided by the # of numbers.
There are 6 numbers.
51 + 60 + 80 + 32 + 47 + 30 = 300
300/6 = 50
Therefore, the answer is A.
Answer:
Dimes = x = 52
Nickels = y = 39
Step-by-step explanation:
Let
Dimes = x
Nickels = y
x + y = 91 (1)
0.10x + 0.05y = 7.15 (2)
From (1)
x = 91 - y
Substitute x = 91 - y into (2)
0.10x + 0.05y = 7.15
0.10(91 - y) + 0.05y = 7.15
9.10 - 0.10y + 0.05y = 7.15
- 0.10y + 0.05y = 7.15 - 9.10
-0.05y = -1.95
y = -1.95 / 0.05
= 39
Substitute y = 39 into (1)
x + y = 91
x + 39 = 91
x = 91 - 39
x = 52
Dimes = x = 52
Nickels = y = 39