Probability

There are 24 df.

That's not a question; indeed, it isn't even a sentence. If you're looking for a lesson to teach to 4th-graders, you might try an educators' site instead.

There is a 2/6 probability of that happnening

i think 6 out of 9 right? then you simplify to equal 1 out of 3.:)

z score = (400-500)/80=-1.25

probability under curve to right of -1.25 = .8944

Yes a Z score can be 5.

Standard deviation can be greater than the mean.

Each toss has 2 outcomes; so the number of outcomes for 3 tosses is 2*2*2 = 8

There are 25 or 32 possible outcomes can you get by tossing 5 coins.

the first seven Fibonacci numbers are 1,1,2,3,5,8,13. 13 is a Fibonacci number.

X = 50 => Z = (50 - 70)/12 = -20/12 = -1.33

So prob(X < 50) = Prob(Z < -1.33...) = 0.091

A deck of cards has 52 cards (not counting jokers which are optional). so if you draw one card at random you have one chance in 52 of getting a specific card. 1/52 = 1.923%

Of course it is.

The first draw always has 10 possibilities. The difference comes in the second draw.

The second draw has 10 possibilities if the first one was replaced, but only 9 possibilities

if the first one wasn't replaced.

No, independence means they are not related. Mutually exclusive means they cannot occur at the same time.

We can certainly simplify that term. 6x - 3x = 3x. And -4y + y = -3y. So the simplified expression is 3x-3y. You could also call this 3(x-y). That's as far as we can go, since we have no way to evaluate x or y without further information.

1 in 224, which is 1 in 16777216.

probability of rolling a 3 = 1/6

probability of flipping a head = 1/2

therefore, overall = 1/12

12/27 reduces to 4/9

numerator = the number of acceptable outcomes

denominator = total number of outcomes (12 boys + 15 girls)

19

four out of seven times

T r+1 = (n / r) (a ^n-r) x (b)^r

standard deviation

two; success or failure

25.55 and 25.65. Because a number of ounces is normally rounded and therefore, the value of the actual number of ounces could be anywhere between 25.55 up to (but not including) 25.65.

No.