Answer:
Part 1) 
Part 2) 
Part 3) 
Part 4) 
Part 5) 
Part 6) 
Step-by-step explanation:
Part 1) we know that
The shaded region is equal to the area of the complete rectangle minus the area of the interior rectangle
The area of rectangle is equal to

where
b is the base of rectangle
h is the height of rectangle
so



Part 2) we know that
The shaded region is equal to the area of the complete rectangle minus the area of the interior square
The area of square is equal to

where
b is the length side of the square
so



Part 3) we know that
The area of the shaded region is equal to the area of four rectangles plus the area of one square
so



Part 4) we know that
The shaded region is equal to the area of the complete square minus the area of the interior square
so



Part 5) we know that
The area of the shaded region is equal to the area of triangle minus the area of rectangle
The area of triangle is equal to

where
b is the base of triangle
h is the height of triangle
so



Part 6) we know that
The area of the shaded region is equal to the area of the circle minus the area of rectangle
The area of the circle is equal to

where
r is the radius of the circle
so


Let's first break it down to the time 8 people need for one wall. That would be 10 minutes, right? If one person would have to do it in stead of 8, you'd expect him to take 80 minutes.
To paint 7 walls, he would nee 7x80 = 560 minutes. 10 people would do that 10 times faster, ie., 56 minutes.
I know puzzles like these always have a mindtrick. Did I miss anything?? ;-)
Answer:
The shadow is decreasing at the rate of 3.55 inch/min
Step-by-step explanation:
The height of the building = 60ft
The shadow of the building on the level ground is 25ft long
Ѳ is increasing at the rate of 0.24°/min
Using SOHCAHTOA,
Tan Ѳ = opposite/ adjacent
= height of the building / length of the shadow
Tan Ѳ = h/x
X= h/tan Ѳ
Recall that tan Ѳ = sin Ѳ/cos Ѳ
X= h/x (sin Ѳ/cos Ѳ)
Differentiate with respect to t
dx/dt = (-h/sin²Ѳ)dѲ/dt
When x= 25ft
tanѲ = h/x
= 60/25
Ѳ= tan^-1(60/25)
= 67.38°
dѲ/dt= 0.24°/min
Convert the height in ft to inches
1 ft = 12 inches
Therefore, 60ft = 60*12
= 720 inches
Convert degree/min to radian/min
1°= 0.0175radian
Therefore, 0.24° = 0.24 * 0.0175
= 0.0042 radian/min
Recall that
dx/dt = (-h/sin²Ѳ)dѲ/dt
= (-720/sin²(67.38))*0.0042
= (-720/0.8521)*0.0042
-3.55 inch/min
Therefore, the rate at which the length of the shadow of the building decreases is 3.55 inches/min
12(3w+8)=25
36w+96=25 ( I used the distributive property)
-96 . -96
36w=-71
w=-1.972222.... ( I divided both sides by 36)
Answer:
ITS CORRECT
Step-by-step explanation:
THE ANSWER IS 0.02 OR 1/50