Answer:
9.11*10^-4 %
Step-by-step explanation:
To find the probability, you simply need to find the possible outcomes that allows no rooks to be in danger, and the possible amount of ways to place the rooks.
For the first outcome, you start by putting 1 rook in the first columns, you have 8 possible rows to do this. The next rook in the next column will only have 7 possible rows, as you have to exclude the one where the previous rook is located. The next rook, 6 possibilities, the next 5, and so on. So we conclude that the total amount of ways so that none of the rooks can capture any of the other rooks is 8*7*6*5*4*3*2*1 = 8! = 40320
In order to find the total amount of ways to place the rooks, you can just use a combinatoric:
![\left[\begin{array}{ccc}64\\8\end{array}\right]= \frac{64!}{8!(64-8)!} = 4.43*10^9](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D64%5C%5C8%5Cend%7Barray%7D%5Cright%5D%3D%20%5Cfrac%7B64%21%7D%7B8%21%2864-8%29%21%7D%20%3D%204.43%2A10%5E9)
Then:
P = 
Answer:
The easiest approach is to realise that one hour is 3 times longer than 20 minutes. The longer the time, the more they will pave.
215 of a mile, in 20 minutes, how much in 60 minutes?#
They will pave 3 times more.
215×31=615 of a mile
615=25 of a mile
You could also use the 'unitary method' where you find out how much they pave in ONE minute (divide by 20) and them multiply by 60 to find how much in one hour.
Look at what happens:
215÷20×60
=215×120×603
=215×3 ← exactly the same maths.
=25
In order to determine the correct answer, it would be helpful to set up equations. We do as follows:
Let x = students
y = adults
x + y = 215
.50x + 2y = 250
SOlving simultaneously, we have:
x = 120 students
y = 95 adults
Hope this answers the question. Have a nice day.
Answer: y = I x l + 1/2
Step-by-step explanation:
Answer:
It is actually A
Step-by-step explanation:
1. E
2.D
3.G
4.E
5.N
6.U
7.I
8.T
10.Y
