Answer:
5
Step-by-step explanation:
for the first gear
revolutions/teeth
1 / 24
2 / 48
3 / 72
4 / 96
5 / 120
6 / 144
for the second gear
revolutions/teeth
1 / 40
2 / 80
3 / 120
4 / 160
<em>the two marks will meet after 120 teeth, 5 revolutions of the first gear and 3 revolutions of the second.</em>
the way to get that amount of teeth is


the Least Common Multiple equals the product of all factors, but those factors who are repeted for both numbers should be only once.

120 teeth are 5 revolutions for gear1 and 3 por gear2
Answer:
19.4 feet
Step-by-step explanation:
When calculating distances using perpendicular angles, we use trig functions such as Sin, Cos, and Tan.
- Sine is defined in a perpendicular triangle as the ratio of the opposite side to the angle over the hypotenuse.
- Cosine is defined in a perpendicular triangle as the ratio of the adjacent side to the angle over the hypotenuse.
- Tangent is defined in a perpendicular triangle as the ratio of the opposite side over the adjacent side.
Because our angle and know side value are across from each other and we need to know the hypotenuse, we chose to use Sine.
We set up the equation
.
We isolate h by multiplying h across the equal sign and dividing sin (68) across as well. 
And finally we have
. We input to calculator.

See the attached picture below showing the shore with the boat out at sea and the position of the person.
Answer:
The probability is 
Step-by-step explanation:
We can divide the amount of favourable cases by the total amount of cases.
The total amount of cases is the total amount of ways to put 8 rooks on a chessboard. Since a chessboard has 64 squares, this number is the combinatorial number of 64 with 8,
For a favourable case, you need one rook on each column, and for each column the correspondent rook should be in a diferent row than the rest of the rooks. A favourable case can be represented by a bijective function
with A = {1,2,3,4,5,6,7,8}. f(i) = j represents that the rook located in the column i is located in the row j.
Thus, the total of favourable cases is equal to the total amount of bijective functions between a set of 8 elements. This amount is 8!, because we have 8 possibilities for the first column, 7 for the second one, 6 on the third one, and so on.
We can conclude that the probability for 8 rooks not being able to capture themselves is

To find the greatest common factor of 40 and 27, we can first start by making a list of factors for each number.
The factors of 27 are: 1, 3, 9, 27
The factors of 40 are: 1, 2, 4, 5, 8, 10, 20, 40
When looking at these numbers, we can see that 1 is the greatest common factor of both 40 and 27.
Hey!
Hope this helps...
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
x + y = 3
x = 3 - y
y = 2x - 15
y = 2(3 - y) - 15
y = 6 - 2y - 15
y = -2y - 9
3y = -9
y = -3
y = 2x - 15
-3 = 2x - 15
-2x = -12
x = 6
So...
The answer is: (6, -3)