The pertinent formula for the circumference of a circle with diameter d is
C =pi*d.
Thus, if the dia. is 6 inches, the circumf. is C = 6pi inches. Alternatively, if we let pi = 3.14, the circumf. is C = 6*3.14 (answer A).
Answer: a. 1759.52 radians/minutes
b. 1407.62 feet/minutes
Step-by-step explanation:
Diameter = 1.6 feet
Radius = Diameter/2= 1.6/2 = 0.8 feet
N = 280 revolution
a. Angular speed(w) = 2πN
= 2π × 280
= 560π
= 560 × 3.142
= 1759.52 radians/minutes
Speed of cyclist = wr
= 1759.52 × 0.8
= 1407.62 feet/minutes
so 5 people work each one for 21 minutes, that means 21+21+21+21+21 minutes altogether, namely 105 minutes, it took that long for 7 walls, hmmmm how long for just one wall then? well, 105 ÷ 7, namely 15 minutes then, for just 1 wall.
now, if it takes 15 minutes of work to do one wall, what about 5 walls? well, that'd be 15*5 or 75 minutes.
so if we have 3 folks working, how much would each one work? well, 75 ÷ 3, namely 25 minutes, so each of them will work 25 minutes, namely 25+25+25 minutes, so in 25 minutes, they'll be done with 5 walls.
Answer:
a) 
D. 9.74
b) 
B. 74
Step-by-step explanation:
Part a
We have the following dataset given:
69 74 75 62 70 93 64 69 61 88 67 77 87 90 66 91 77 63 82 82 71 74 76 65 83
We can begin calculating the sample mean with the following formula:
And replacing we got:
Now we can calculate the sample deviation with the following formula:
And after replace we got:
Part b
For this case we need to sort the value on increasing way:
[1] 61 62 63 64 65 66 67 69 69 70 71 74 74 75 76 77 77 82 82 83 87 88 90 91 93
And the median would be the value in the position 13 and we got:
