Ask for junior high school math probability problems, there are detailed steps 349 3

List all possible scenarios as follows: u n

i v e r

s l solution: There are 9*4+8*5=76 equal possible results.

1)p=(4*4) 76=16 76=4 192) p=(5*4+5*4) 76=40 76=10 19 pro, I hope mine can help you, remember!

The probability of drawing the first consonant ball in the first sub-question is 5 9 right, and the probability of the second consonant ball being drawn is 4 8, because it is not put back, so according to the principle of multiplication, the probability is 5 18, and so on - the second question is not to draw two balls. Probably not, right?

Total number of 22 (1 3) = 66

After joining, the number of people is 66 + 14 = 80

The number of people who do not have it is 66-22=44

The probability of not having it is 44 80 = 11 20,8, ask for junior high school math problems, there are detailed steps Oh Probability Oh 133 11

In a youth club, its members 22 own sports cars.

If a member is chosen at random, the probability that he or she will have a sports car is 1 3Another 14 young people who own sports cars then join this club.

If a Blind Priest is now chosen at random, calculate the probability that he will lose money to her and not own a sports car.

(1) The second time you get the red ball, that is, "the first time you get the white ball, and the second time you get the red ball", the probability is 2 3x1 2=1 3

2) Algorithm 1: 1-p (get the white ball twice) = 1-2 3x1 2=2 3 algorithm 2: p (get the red ball for the first time) = p (get the red ball for the first time, get the white ball for the second time) + p (get the white ball for the first time, and get the red ball for the second time) = 2 3x1 2+2 3x1 2=2 3

To sum up, the probability of getting a red ball for the second time is 1 3, and the probability of getting a red ball is 2 3

Please adopt, thank you!

Simplify the problem, divided into two touches, it doesn't matter what macro damage the pin boy touched the first time, the key is the second time, the second time to touch the medicine and the first time to match a pair, now there are 7 gloves in the bag, and the first pair is only two, (because there are two pairs are the same bucket preparation), so its probability is 2 7

1. There are four balls in total, there are three red balls, the probability of touching the red ball is 3 4, and the probability of touching one is put back, and then the probability of Mo red ball is still 3 4, so the probability of touching the red ball is (3 4) * (3 4) = 9 16

2. Similarly, the probability of touching a red ball first is 3 4, and then there are three balls, two reds, and then the probability of touching a red ball is 2 3, so the probability of touching two red balls is (3 4) * (2 3) = 1 2

(1) Two independent events, each time the probability is 3 4

p=3 /4x3/4=9/16

2) There are 2 possibilities for finding two balls, and the possibility for the red ball is c3 2p=c3 2 c4 2=3 6=1 2

A: 6*8 24*3=6

B: 3*4 36*2=2 3

Shoot 6 3-pointers, i.e. 10 seconds, 2 3 shots, 20 seconds, 60 seconds.

Set the number of 2-point shots x the number of 3-point shots is y, there are 3 cases of 0, 6, 1, 4, 2, 2, 3, 0 are calculated separately.

To make x*4 36 + y*8 24 maximum, i.e. 6 13 9 5 9 2 3

So the best way to do this is to shoot all of Team A.

Solution, take red 1 red 1, red red 1 red 1 red, red red 1 red red 1, red 1 red 1 red red, red 1 red red 1, red 1 red red 1, 6 kinds.

There are 6 types of pink and 6 types of green.

then n=6x6x6=216 species.

There are 4 of each color, because they are not complex and connected of the same color, such as green-green, green-green 1, green 1; Another green can also be: green-green, green-green 1, green-green 1. Each of them has 3 ways to connect, that is, 3 possibilities, so there are 48 ways to connect, as follows:

Green-green, green-green 1, green-green, green-green, green-green-1, green-green-1, green-1, green-1, green-1, green-1, green-1-green, green-1-green. The rest of the pink and red are the same, but with a different color, I won't write them down one by one.