A standard number cube has 6 sides labeled 1 to 6. apu rolls a standard number cube 30 times. How many times can
he expect to roll a 5 or 6?

The expected value of rolling a 5 or 6 is 10.

Step-by-step explanation:

The sample space of rolling a standard number cube is:

S = {1, 2, 3, 4, 5 and 6}

The cube is standard, this implies that each side has an equal probability of landing face-up.

So, the probability of all the six outcomes is same, i.e. .

Now it is provided that Apu rolls the cube n = 30 times.

Let the random variable X represent the value on the face of cube.

The event of rolling a 5 and rolling a 6 are mutually exclusive, i.e. they cannot occur together.

So, P (X = 5 and X = 6) = 0.

Compute the probability of getting a 5 or 6 as follows:

P (X = 5 or X = 6) = P (X = 5) + P (X = 6) - P (X = 5 and X = 6)

                            = P (X = 5) + P (X = 6)

Compute the expected value of rolling a 5 or 6 as follows:

Thus, the expected value of rolling a 5 or 6 is 10.

d. bc = 12 and ef = 16

step-by-step explanation:

we are given that δabc : δdef such that .

also, it is given that

so, from the options, we need that .

a.

b.

c.  

d.

as, we can see that only option d gives the same ratio as i.e. .

hence, the possible lengths are bc = 12 and ef = 16.

what are you trying to solve here

step-by-step explanation: