Question

Marco draws a card and replaces it 10 times from a standard deck of 52 cards. He draws 8 red cards and 2 black cards. What is the theoretical probability that he will draw a red card on his 11th draw?
1/4
1/2 ***
2/3
4/5
@acxbox22 @david111

Answer 1

the theoretical probability of the next card being red is 1/2

and the previous results have no influence of the next draw... this is know as independent events

Answer 2

@campbell_st thank you .

Answer 3

A fire department has determined that on any particular day there is a 20% chance that it will have to respond to a call. What is the probability (to the nearest whole percent) that during any 3-day span it will have to respond to a call AT LEAST once?

Answer 4

@david111 @acxbox22 @campbell_st

Answer 5

is is this a quiz you are doing...?

Answer 6

@campbell_st . No it is a EOCT review sheet . ** hence the fact I am asking for HOW to go about solving these questions.

Answer 7

the opposite of at least once is no call
prob (no call) for 3 days = 0.8^3

prob ( at least one call) = 1 - 0.8^3 = 0.488 = 48.8 %
answer B : 49 %

Answer 8

well use the complementary events

P(At least 1) = 1 - P(0 calls for the 3 days)

Answer 9

@david111 how did you get 0.8^3

Answer 10

Probability of a call = 0.2
Probability of no call = 1 - 0.2 = 0.8

P(no call day 1) = 0.8
P(no call day 1 and 2) = P(no call day 1)*P(no call day 2) = 0.8*0.8 = 0.8^2
P(no call day 1 and 2 and 3 ) = 0.8*0.8*0.8 = 0.8^3

Answer 11

@kirbykirby thank you for explaining that .
so my answer is 49% ?

Answer 12

yes

Answer 13

@david111 wait .. how did you know it was answer choice B ? I didn't post the choices .. lol

Answer 14

Yes, but wonder where @david111 got option B from o_O?

Answer 15

im a genius i can read ur mind

Answer 16

@kirbykirby same here .. you copied and pasted lmaoo .

Answer 17

nope i can see ur worksheet

Answer 18

im in a tree with binoculars

Answer 19

stalk much

Answer 20

lol

Answer 21

Mary Katherine draws a card and replaces it 50 times from a standard deck of 52 cards. She records her results and gets 20 red cards and 30 black cards. What is the experimental probability of selecting a black card on her next draw?
1
2/5
3/5 ***
3/4

Answer 22

She's got 30 blacks and 20 reds. So her experimental probability is 30/50 = 0.6 (while the theoretical probability is 0.5).

Answer 23

She got black 30/50 times so simplify to 3/5

Answer 24

@david111 the answers are in fraction form .

Answer 25

way ahead of you.

Answer 26

choices?

Answer 27

I already put them .

Answer 28

how many questions do you have left?

Answer 29

3/5 is awsner.

Answer 30

I have 9 left but I know how to do some of them on my own .

Answer 31

responsibility