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:
14
Step-by-step explanation:
This is a division problem.
We want to find how many 1/3 liters are in 4⅔ liters.
We divide to obtain:
Or
Convert to improper fraction.
This simplifies to
Therefore there are fourteen ⅓ liters in 4⅔ liters
Answer: 0.6 in 10 % ; 0.4 in 15 %
Step-by-step explanation:
1. (x*10%) + (y*15%)/ x+y=12%
2. x+y = 1 x= 1-y
(0.1x + 0.15y/ x+y= 12/100) * 100
(10x + 15y/x+y = 12)*(x+y)
10x+15y= 12x + 12y
-2x=-3y
2x = 3y 2(1 - y)= 3y
2-2y=3y 2= 5y
y= 0.4
x= 0.6
Answer:
Step-by-step explanation:
penetrating electromagnetic radiation of a kind arising from the radioactive decay of atomic nuclei.
