Answer:
A person can select 3 coins from a box containing 6 different coins in 120 different ways.
Step-by-step explanation:
Total choices = n = 6
no. of selections to be made = r = 3
The order of selection of coins matter so we will use permutation here.
Using the formula of Permutation:
nPr = 
We can find all possible ways arranging 'r' number of objects from a given 'n' number of choices.
Order of coin is important means that if we select 3 coins in these two orders:
--> nickel - dime - quarter
--> dime - quarter - nickel
They will count as two different cases.
Calculating the no. of ways 3 coins can be selected from 6 coins.
nPr = = 
nPr = 120
さたはたはたはたはたはたはたはたはたはたしたはあらさたはたはてはありはあはあはあらありあは
Answer: 
or 
Step-by-step explanation:
The volume of a cylinder can be found with the following formula:
Where "r" is the radius and "h" is the height of the cylinder.
In this case, let be:
- 
the volume of one of this cylinders and 
the volume of the other one.
- 
the radius of the first one and 
the radius of the other cylinder.
- 
the height of one of them and 
the height of the other cylinder.
Then:
Therefore, you know this:
Simplifying, you get:
Now, knowing the ratios given in the exercise, you can substitute them into the equation:
Evaluating, you get:
8 x 2 1/4 = 18
the stack is 18 in. thick.
Hope this helps!!
~Kiwi
Circumerence=2pir or dpi were r=radius and d=diameter
11pi=2pir
divid eobt sides by pi
11=2r
dvide 2
5.5=r
11pi=dpi
divide both sides by pi
11=d
diameter=11in
radius=5.5 in
