Question:
A = {2, 3, 4, 5}
B = {4, 5, 6, 7, 8}
Two integers will be randomly selected from the sets above, one integer from set A and one integer from set B. What is the probability that the sum of the two integers will equal 9?
A. 0.15
B. 0.20
C. 0.25
D. 0.30
E. 0.33
Answer:
Option B: 0.20 is the probability of the sum of the two integers.
Explanation:
The sample space for selecting 2 numbers is given by
We need to determine the probability that the sum of two integers will be equal to 9.
Hence, we need to add the two integers from the sets A and B such that their sum will be equal to 9.
Hence, the sets are 
Thus, the total number of sets whose sum is equal to 9 = 4
The probability that the sum of the two integers will equal 9 is given by
Thus, the probability that the sum of the two integers will equal 9 is 0.20
Hence, Option B is the correct answer.
Ok , with that information we can write the equations
x + y = 6
5x + 4y = 28
Where x = how many people ordered chicken
and y = how many people ordered egg salad
Through elimination , we can set one of the variables in both equations equal so we can eliminate it :
(4)x + (4)y = (4)6
5x + 4y = 28
4x + 4y = 24. equation 1
5x + 4y = 28. equation 2
Now we can subtract the second equation by the first equation and isolate one variable:
equation 2 - equation 1
5x - 4x + 4y - 4y = 28 - 24
x = 4
Now that we discovered our x value ( How many people ordered chicken salad ) , we can apply it to one of the equations and discover y ( how many people ordered egg salad)
x + y = 6
x= 4
4 + y = 6
We can shift 4 to the other side of the equation by subtracting 4 from both sides of the equation:
4 - 4 + y = 6 - 4
y = 2
x=4 and y=2
So the awnser is :
4 people ordered chicken salad and 2 people ordered egg salad!
I hope you understood my brief explanation!!
p.s if you want to know how to use another method to solve these problems ( Substition) , just let me know in a comentary down here
True. If there is a point in the middle that is false, we have two create 2 solutions.
Hope this helps!
I think it would be D because it started off low then it started to increase
