Correct question:
An urn contains 3 red and 7 black balls. Players A and B withdraw balls from the urn consecutively until a red ball is selected. Find the probability that A selects the red ball. (A draws the first ball, then B, and so on. There is no replacement of the balls drawn).
Answer:
The probability that A selects the red ball is 58.33 %
Step-by-step explanation:
A selects the red ball if the first red ball is drawn 1st, 3rd, 5th or 7th
1st selection: 9C2
3rd selection: 7C2
5th selection: 5C2
7th selection: 3C2
9C2 = (9!) / (7!2!) = 36
7C2 = (7!) / (5!2!) = 21
5C2 = (5!) / (3!2!) = 10
3C2 = (3!) / (2!) = 3
sum of all the possible events = 36 + 21 + 10 + 3 = 70
Total possible outcome of selecting the red ball = 10C3
10C3 = (10!) / (7!3!)
= 120
The probability that A selects the red ball is sum of all the possible events divided by the total possible outcome.
P( A selects the red ball) = 70 / 120
= 0.5833
= 58.33 %
Answer:
x can take any value and are viable in this situation if and only if it is a positive number
Step-by-step explanation:
We know that the area of a rectangle is given by:
A = x * y
So if we replace we have:
12 ≤ x * y ≤ 36
We divide by y, and we have:
12 / y ≤ x ≤ 36 / y
Which means that the value of x depends on y, that is to say if y is worth 1, the inequality would be:
12 ≤ x ≤ 36
In the event that y is equal to 2:
12/2 ≤ x ≤ 36/2
6 ≤ x ≤ 18
Which means, that depending on y, x can take any value and are viable in this situation if and only if it is a positive number.
<u>Answer:</u>
C. Left-handed: 48, Right-handed: 504
D. Left-handed: 30, Right-handed: 315
<u>Step-by-step explanation:</u>
We are given that there are 58 left-handed students and 609 right-handed students at East Middle School and these numbers of students are proportional to the number of left and right handed students at East Middle School.
Given the above information, we are are to determine which two options could be the the numbers of left-handed and right-handed students at West Junior High.
Ratio of right handed to left handed students at East Middle School = 
Checking for ratios of the given options:
A. 
B. 
C. 
D. 
E. 
Therefore, the possible numbers of left-handed and right-handed students at West Junior High could be C. Left-handed: 48, Right-handed: 504 and D. Left-handed: 30, Right-handed: 315.
Possible outcomes :
Heads Heads
Heads Tails
Tails Tails
Tails Heads
Probability of matching : 2/4 = 0.5
Torin should agree since the proposal is fair