Answer:
b) 2.7632
Step-by-step explanation:
To find the mean, we multiply each value by it's probability. So
So the correct answer is:
b) 2.7632
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:
1242 6th graders went on the trip.
Step-by-step explanation:
From the information given, you know that the theater has 2760 seats and that the students filled 45% of the seats, so to find the quantity of 6th graders that went on the trip, you have to calculate 45% of 2760:
2760*45%=1242
According to this, the answer is that 1242 6th graders went on the trip.
Answer:
35 is the integer that represents the change in number of gallons of water in the tank after 7 days
Step-by-step explanation:
The water tank leaks 5 gallons in one day.
So if there is leakage of 5 gallons a day, then after 7 days the total leakage will be:
Total Leakage = Leakage per day * Total number of days
= 5 Gal/day * 7 day
= 35 Gallons
So, 35 is the integer that represents the change in number of gallons of water in the tank after 7 days ..
Answer
1/9
Step-by-step explanation:
the chance that she gets it one day is 1/3 so you multiply that by 1/3 because there are three days.
