Answer:

Step-by-step explanation:
Let
be the shaded area and
be the unshaded area, then we know that
(1). 
and
(2).
We solve for
in the first equation and get:

and put this into the second equation and get:




Answer is C:1/3
21 total
7/21=1/3
The 6 people be assigned in 720 different ways to chair the subcommittees.
<u>Step-by-step explanation:</u>
Given that,
- There are 6 people to be assigned to the chair committees.
- So, you need to find that in how many ways they can be assigned their seats.
This can be calculated by Permutation.
The number of arrangements in which the order of the objects matters is calculated as permutation.
The permutation is given as ⇒ P = n!
Here we can 6 people to be assigned. Therefore n = 6.
⇒ Number of ways can be arranged = 6!
⇒ 6×5×4×3×2×1
⇒ 720
∴ The 6 people be assigned in 720 different ways to chair the subcommittees.
Answer:
r = 21
Step-by-step explanation:
The "one step" is to undo the division by 3. To undo that division, you multiply both sides of the equation by 3. this gives you ...
r·(3/3) = 7·3
r = 21
_____
The basic idea of any equation solution process is to "undo" what has been done to the variable. This is where the multiplication and addition identity elements come into play.
In this problem, the variable is multiplied by 1/3. The number that you multiply this by to get the identity element for multiplication (1) is the inverse of this fraction: 3/1, or 3. That is, 3 × 1/3 = 3/3 = 1. When 1 multiplies r, the result is just r, which is what you're trying to get to.
The rules of equality tell you that whatever you do to one side of an equation, you must also do to the other side. If you multiply r/3 by 3 on the left, then you must also multiply 7 by 3 on the right to keep the equation a true statement.
_____
<em>If the "one-step" involves addition ...</em>
If the equation had been ...
r + 3 = 7
Then the operation you need to "undo" is the addition of 3. That is accomplished by adding -3 to both sides of the equation. Then you have ...
r + 3 - 3 = 7 - 3
r + 0 = 4
r = 4
You will recognize 0 as the additive identity element: r + 0 = r. In order to get that (0) as a sum, you need to add opposites: +3 -3 = 0. Again, you have to do the same thing (add -3) to both sides of the equation in order to keep it true.