Question

Find the missing probability in the table below.
X 1 2 3 4
P(X) 0.40 0.20 0.20 ?

Answer 1

All probabilities must add to 1 in a probability distribution

Answer 2

So if y is the missing probability, then

0.4+0.2+0.2+y = 1

Answer 3

I don't understand..

Answer 4

add up 0.4, 0.2, and 0.2

Answer 5

0.8?

Answer 6

so there's an 80% chance that X is either 1, 2, or 3

Answer 7

what's left over?

Answer 8

20%? I think

Answer 9

yes, there's a 20% chance of X = 4 since that's the only thing left

Answer 10

so the missing probability is 0.2

Answer 11

0.2! Got it thanks ! (:

Answer 12

Can i bother you with another question?

Answer 13

You can't have anything greater than 20% since you can't go over 100%

and you can't have anything under 20% because if you fall short of 100%, then that suggests there is another possibility....when there clearly isn't

so it has to be 20%

Answer 14

sure go for it

Answer 15

Given the table of M&M® distributions below, find P(not orange), the probability of selecting anything but a orange M&M at random from a large bag.
Red Orange Yellow Green Blue Brown
0.13 0.20 ? 0.16 0.24 0.13

Answer 16

those are all the possibilities and you can't choose anything else

eg: you have a 13% chance of choosing Red. You have a 24% chance of choosing blue

Answer 17

so add up all the given probabilities

Answer 18

OKay hold onn

Answer 19

0.86

Answer 20

So i would subtract that from .1?

Answer 21

so the missing probability must be what

Answer 22

from 1 not 0.1

Answer 23

Is .14 the answer?

Answer 24

no, but it helps get you there

Answer 25

Shoot.

Answer 26

they want to know the probability of choosing anything but orange

Answer 27

so add up all the probabilities that correspond to anything but orange

Answer 28

so add the probabilities for red, yellow, green, blue, brown

Answer 29

Okay i got 0.8

Answer 30

Which is 80%

Answer 31

good, so the answer is 0.8

Answer 32

A thousand times thank you!

Answer 33

which corresponds to an 80% chance of selecting something that isn't orange

Answer 34

yw