Let's call the stamps A, B, and C. They can each be used only once. I assume all 3 must be used in each possible arrangement.
There are two ways to solve this. We can list each possible arrangement of stamps, or we can plug in the numbers to a formula.
Let's find all possible arrangements first. We can easily start spouting out possible arrangements of the 3 stamps, but to make sure we find them all, let's go in alphabetical order. First, let's look at the arrangements that start with A:
ABC
ACB
There are no other ways to arrange 3 stamps with the first stamp being A. Let's look at the ways to arrange them starting with B:
BAC
BCA
Try finding the arrangements that start with C:
C_ _
C_ _
Or we can try a little formula; y×(y-1)×(y-2)×(y-3)...until the (y-x) = 1 where y=the number of items.
In this case there are 3 stamps, so y=3, and the formula looks like this: 3×(3-1)×(3-2).
Confused? Let me explain why it works.
There are 3 possibilities for the first stamp: A, B, or C.
There are 2 possibilities for the second space: The two stamps that are not in the first space.
There is 1 possibility for the third space: the stamp not used in the first or second space.
So the number of possibilities, in this case, is 3×2×1.
We can see that the number of ways that 3 stamps can be attached is the same regardless of method used.
Answer:
The constant force exerted on the ball by the wall is 119.68 N.
Step-by-step explanation:
Consider the provided information.
It is given that the mass of the ball is m = 2.2 kg
The initial velocity of the ball towards left is 7.4 m/s
So the momentum of the ball when it strikes is = 
The final velocity of the ball is -6.2 m/s
So the momentum of the ball when it strikes back is = 
Thus change in moment is: 
The duration of force exerted on the ball t = 0.25 s
Therefore, the constant force exerted on the ball by the wall is:
Hence, the constant force exerted on the ball by the wall is 119.68 N.
Answer:
Step-by-step explanation:
Given that the population of a city increased steadily over a ten-year span. The following ordered pairs show the population x and the year y over the ten-year span in the form (x, y) for specific recorded years.
x y
2500 2001
2650 2002
3000 2004
3500 2007
4200 2011
Slope 0.005865485
Intercept 1986.406413
So regression line is
When population = 15000
Answer:
1/5
Step-by-step explanation:
there are 5 groups
1. 1-9
2. 10-19
3.20-29
4.30-39
5.40-49
and 50
