Answer:
1/72
Step-by-step explanation:
Answer: 28.26
Step-by-step explanation:
What your looking for is called the annulus (or the difference of two concentric circles). You can find the annulus by subtracting the area of the inner circle from the area of the outer circle. Volume of a circle= πr²
You are given the diameter in these problems, so you need radius.
For the first circle (8 in one) :
8/2=4 r=4
A=3.14(4)²
A=50.24
For the second one (10 in one) :
10/2=5 r=5
A=3.14(5)²
A=78.5
To find the measure of the annulus, you subtract those numbers, getting 28.26
Answer:
138 cm.
Step-by-step explanation:
So first, we find the S.A. of the front and back.
The diagram says the side length of the front is 3 cm. and 3 cm.
3x3=9. So then, the back is also 9 cm, 9+9=18.
Now to find the S.A.'s of the four sides, you have to see the side lengths of each of them. The side lengths are 3 and 10.
3x10=30. This means each of them is 30 cm.
30x4=120. 120 is the total surface area of the four sides.
To find the total surface area of the whole rectangle, you add all the surface areas.
120+18=138 cm. (Not squared, since it's surface area and not area.)
Step-by-step explanation:
Initial expression = 80 + 78 + (-97) + 12
final expression = 170-97 ==> $73
