Answer:
4/91
Step-by-step explanation:
There are a total of 15 marbles. In the first selection there are 15 marbles and 6 are blue. That would be 6/15.
Since we are not replacing marbles, we now have 14 marbles and we want to select one of the 5 white marbles. That would be 5/14.
Lastly we now only have 13 marbles and of those we want to select one of the 4 red ones. That would be 4/13.
Now we take these 3 fractions and multiply them together.
6/15(5/14)(4/13). I am going to try to make this a little easier and see if I can find any factors that any top number shares with any bottom number.
I see 5 on the top shares a common factor with 15 on the bottom. I will divide these numbers by 3, so now I have
6/3(1/14)(4/14). I think that I can do better than that. I see that 6 on the top and 3 on the bottom share a common factor of 3. I will divide both of these numbers by 3. Which will give me:
2/1(1/14)(4/13) I see a 4 on top and a 14 on the bottom. Those are both divisible by 2 so, I will divided them both by 2 and that leaves me with
2/1(1/7)(2/13) That is a lot easier, now I will just multiple the top numbers and multiply the bottom numbers to get
4/91
Consider the point P where the gears meet. When the smaller gear rotates clockwise, the larger one will rotate counterclockwise.
Through one rotation of the smaller gear, P will have traveled the circumference of the smaller gear, which is in.
At the same time, a point P' on the larger gear traverses the same distance along the larger gear's circumference. This point traces out an arc that is subtended by some angle . The arc is as long as the smaller gear's circumference.
The measure of a circle's interior angle subtended by an arc is proportional to a complete revolution, i.e. an angular displacement of radians:
For part 2, we apply the same reasoning to the larger gear. In one full rotation of the larger gear, the point P' traverses the circumference in, and so does the point P on the smaller gear.
A full rotation is 360 degrees, so the smaller gear would have rotated times.
Answer:
3031081 / 40678884
Step-by-step explanation:
To solve this, we can find the surface area of the moon and Earth, and then see how much the moon covers the Earth. The surface area of a sphere is equal to 4πr², so the radius of the Earth is
4πr² = 4 * π * 6378²
and the radius of the moon is
4πr² = 4 * π * 1741²
To figure out how much of the Earth's surface that the moon covers, we can implement a ratio of moons:Earth. This will give us an understanding of how many moons go inside one Earth. We thus have
(4 * π * 1741²) : ( 4 * π * 6378²) = (4 * π * 1741²) / ( 4 * π * 6378²)
cross out the 4 * π in the numerator and denominator
1741²/6378²
Next, we want to make the denominator 1, as that gives us 1 Earth. To do this, we can divide both the numerator and denominator by 6378². Because we are applying the same expression to both the numerator and denominator, this is essentially multiplying the fraction by 1, keeping it the same. We thus have
(1741²/6378²)/(6378²/6378²)
≈0.0745/1
≈ 0.0745
To put this in a fraction, we would have
(1741²/6378²)/1
= (1741²/6378²)
= 3031081 / 40678884
0.75/1.5 = x/1
1.5x = 0.75
x = 0.5 cups
1/2 cup of flour is needed for 1 dozen cookies
Answer:
it is 4 feet deep
Step-by-step explanation: