Answer:
Step-by-step explanation:
22/7x4^2=50.28
3x3=9
50.28-9=41.28
Answer:
21 windows
Step-by-step explanation:
collen family plans to paint the windows of their house. her father will paint twice as many windows as her mother, and collen and her 2 brothers will paint an equal number of the rest of the windows. Colleen decided to do her own share and her mother's share and paints 7 window, which is one less than her father's share. how many windows are in their house?
Answer: Let the number of window Collen father would paint be a while that of her mother be b. Since her father will paint twice as many window as her mother, therefore the number of windows painted by the father a = 2b
Let the number of windows that would be needed to be painted each by Colleen and her 2 brothers be c because they would paint the equal number of windows.
The total number of windows to be painted = 2b + b + c + c + c = 3b + 3c = 3(b + c).
Collen painted 7 windows as her mother and her own share which is one less than the fathers share. Therefore b + c = 7.
Also the fathers share a = 2b = 7 + 1 = 8 windows. Therefore b = 4 which is the mother share
Therefore the total number of windows = 3(b + c) = 3(7) = 21 windows
3b + 3c = 21
3(4) + 3c = 21
12 + 3c = 21
3c = 21 - 12
3c = 9
c = 3 which is collen and her brothers share
Answer:
The angular velocity is 6.72 π radians per second
Step-by-step explanation:
The formula of the angular velocity is ω =
, where v is the linear velocity and r is the radius of the circle
The unit of the angular velocity is radians per second
∵ The diameter of the tire is 25 inches
∵ The linear velocity is 15 miles per hour
- We must change the mile to inch and the hour to seconds
∵ 1 mile = 63360 inches
∵ 1 hour = 3600 second
∴ 15 miles/hour = 15 × 
∴ 15 miles/hour = 264 inches per second
Now let us find the angular velocity
∵ ω =
∵ v = 264 in./sec.
∵ d = 25 in.
- The radius is one-half the diameter
∴ r =
× 25 = 12.5 in.
- Substitute the values of v and r in the formula above to find ω
∴ ω = 
∴ ω = 21.12 rad./sec.
- Divide it by π to give the answer in terms of π
∴ ω = 6.72 π radians per second
The angular velocity is 6.72 π radians per second