Indipendent + Dependent events
A die is cast 6 times. What is the probability that each throw will return a prime number?
1/64
P(3)= 1/6
P(6)= 1/6
P(3 or 6)= P(3)+ P(6)=
1/6+1/6
2/6= 1/3
The probability of a die showing a 3 or 6= 1/3
Helen has a bag of marbles which contains 10 red marbles, 8 blue marbles, and 2 yellow marbles. Find the experimental probability of getting a blue marble.
The experimental probability of getting a blue marble from the bag is 6/10= 3/5
When A made a call, he forgot the last digit of the other party's phone number, but remembered that the digit was not "0". The probability that A tries to replace the last digit with another digit, just on the second attempt, is:
1/9
2/5 + 1/8=?
21/40
Two cards are chosen at random from a deck of 52 cards without replacement. What is the probability of choosing two kings?
1/221
The probability of Tina becoming the monitor is 0.2 and the probability of Tania becoming the monitor is 0.4. What is the probability of either Tania or Tina becoming the monitor?
0.6
Magnolia rolled a number cube 24 times and landed on 2 four times and on 6 three times.
A. Find the experimental probability of landing on a 2. B. Find the experimental probability of not landing on a 6.
A. 4/24= 1/6
B. 5/6
When two dice are rolled at the same time.
a) What is the probability that the sum of the dice is 3?
b) When the order counts, What is the probability that both the dice will have a 6?
c) You roll 2 dice. What is the probability that the sum is 6 if at least one of the two numbers is a 5?
A) 2/12= 1/6
B) 1/36
C) There are 2 ways to roll a 6 if at least one number is a 5 and there are 11 ways to roll at least one 5, so the probability is 2/11.
What are the prime numbers 1-30?
2,3,5,7,11,13,17,19,23,29
Tell whether the events are independent or dependent. Explain.
A. You flip heads on one coin and tails on another coin. The outcome of flipping one coin does not affect the outcome of flipping the other coin.
B. Your teacher chooses one student to lead a group and then chooses another student to lead another group. The teacher cannot pick the same student to lead both groups. So, there are fewer students to choose from when the leader of the second group is chosen.
a. Indepenedent
b. Dependent
The probability that Mohammed will receive an A,B,C,D, or E on a test is 0.13, 0.26, 0.45, 0.11 and 0.5 respectively. What is the probability that Mohammed will get the following results?
a) An A or B
b) At least a D
c) Less than A
a) 0.39
b) 0.95
c) 0.87
After Arizona introduced a new juice, a taste test was conducted by the students of CAPS to see how it is being received. Of those who participated, 40 said they preferred the new juice, 92 preferred the old juice, and 68 could not tell any difference. What is the probability that a person in this survey preferred the new juice?
1/5
Tina's Nike shoebox holds a number of disks of the same size. There are 5 red, 6 white, and 7 blue disks. Tania picks out a disk, records its color, and returns it to the box. If you repeat this process 250 times, how many times can you expect to pick either a red or white disk?
about 153
2+5(25/5)2-17=
110
Both places A and B are located in the lower reaches of the Yangtze River. According to the meteorological records of more than 100 years, it is known that the proportion of rainy days in A and B in a year is 20% and 18% respectively, and the proportion of rain in both places is 12%. What is the probability that A is raining when B is raining?
0.67
Tania's pack of poker cards consists of different numbers of white, black, and red cards. If the probability of choosing a white or red card is 0.6 and the probability of choosing a white or black card is 0.7, What is the probability of choosing each of the colored cards individually?
white: 0.3
black: 0.4
red 0.3
For the past 40 days, Helen has been recording the number of customers at her mom's restaurant between 10:00 a.m. and 11:00 a.m. During that hour, there have been fewer than 20 customers on 25 out of the 40 days. What is the experimental probability there will be 20 or more customers on the forty-first day? as a percent
A factory makes bicycles. Out
37.5%
A hat contains 4 marbles; one yellow, one red, and two green. One marble is selected at random without replacement from the hat. What is the probability that this marble selected is
a) green
b) blue
c) yellow
a) 2/4=1/2
b) 0
c) 1/4
(6x4+4x3-2x2+5) - (3x4-2x3+x+4)
3x4+6x3-2x2-x+1
A factory produces a machine tool, and the number of defective machines is one-ninth of the number of genuine machines. After a review in the background, it is found that one of the genuine machine tools is unqualified. At this time, the number of defective machines is 3/22 of the number of genuine machines. How many machines are there in total?
Suppose the original number of genuine units is x
3/22 (x-1)=1/9x+1
3/22x - 3/22= 1/9x +1
3/22x -1/9x= 1 + 3/22
27/198x- 22/198x =25/22
5/198x = 25/22
x= 25/22 ÷ 5/198
x= 45
45 x 1/9= 5
45+5= 50
When throwing dice, record event A as "the number that goes up when the dice hits the ground is an odd number", event B is "the number that goes up when the dice hits the ground is an even number", and event C is "the number that goes up when the dice hits the ground is a multiples of 3". The mutually exclusive events are？
A & B
The accuracy rate of a weather station's weather forecast is 80%, calculating (1) the probability that 5 out of 6 forecasts are accurate; (2) the probability that at least 5 out of 6 forecasts are inaccurate.
1) 5/6*0.8= 2/3
2) 5/6 *0.2= 1/6
There are 25 girls and 27 boys in a class, and two students are randomly selected. What is the probability that they are both girls?
25+27= 52
P1= 25/52
P2= 25-1/52= 24/51
25/52 x 24/51= 600/ 2652= 300/1326= 100/442= 50/221
There is a three-digit number, and the digit in the hundreds place is 1. If 1 is placed in the last digit, and the order of the other two digits remains unchanged, the new number obtained is 234 larger than the original number, and the original three-digit number is obtained.
100+x+234=10x+1