Answer:
D. 2/7
Step-by-step explanation:
The probability is calculate as a division between the number of ways in which Andrew will be selected and karen will not and the total ways in which they can select 4 people from a group of 8 volunteers.
The number of ways in which they can select 4 people from a group of 8 volunteers can be calculated using:

Where nCk give as the number of ways in which we can form groups of k elements from a group of n elements.
So, if we replace n by 8 and k by 4, we get:

Then, there are 70 ways to select 4 people from a group of 8 volunteers.
At the same way, the number of ways in which Andrew will be selected and karen will not can be calculate replacing n by 6 and k by 3 in the same equation as:

We replace n by 6 because from the 8 volunteers, Andrew is going to be selected and Karen will not, so, the people that affect the result are just the 6 remaining volunteers. Also, k is equal to 3 because Andrew is already selected and we just need to select 3 more people.
Finally, the probability is:

1
1x7=7
1+7=8
1 is the answer
<u>Answer</u>
B(18/5,0)
<u>Explanation</u>
First we find the coordinates of C;
C (x, y) = [(-3+7)/2, (2+6)/2]
= (2, 4)
Find the equation of CD.
slope = (6-2)/(7--3)
= 4/10 = 2/5
slope of CD = -5/2
-5/2 = (y - 4)/(x - 2)
-5/2(x - 2) = y - 4
(-5/2) x + 5 = y - 4
y = (-5/2)x + 9
For the x-intercept y = 0
∴ y = (-5/2)x + 9
0 = (-5/2)x + 9
5/2 x = 9
x = 2/5 × 9
= 18/5
x-intercept = (18/5, 0)
Answer:
13 is the answer.
Step-by-step explanation:
Answer:
27 years
Step-by-step explanation:
Given that :
Town A:
Initial population = 14280
Rate = increase by 160 per year
Let t = time in years
Population is thus :
14280 + 160t - - - (1)
Town B:
Initial population = 24000
Rate = decrease by 200 per year
P = 24000 - 200t - - - (2)
Equate both equations :
14280 + 160t = 24000 - 200t
160t + 200t = 24000 - 14280
360t = 9720
t = 9720 / 360
t = 27
In 27 years