Answer:
(a) The expected number of guests until the next one pays by American Express credit card is 4.
(b) The probability that the first guest to use an American Express is within the first 10 to checkout is 0.0215.
Step-by-step explanation:
The random variable <em>X</em> can be defined as the number of guests until the next one pays by American Express credit card
The probability that a guest paying by American Express credit card is, <em>p</em> = 0.20.
The random variable <em>X</em> follows a Geometric distribution since it is defined as the number of trials before the first success.
The probability mass function of <em>X</em> is:

(a)
The expected value of a Geometric distribution is:

Compute the expected number of guests until the next one pays by American Express credit card as follows:



Thus, the expected number of guests until the next one pays by American Express credit card is 4.
(b)
Compute the probability that the first guest to use an American Express is within the first 10 to checkout as follows:


Thus, the probability that the first guest to use an American Express is within the first 10 to checkout is 0.0215.
34 = q + n
6.1 = .25q + .05n
-1.7 = -.05q - .05n
6.1 = .25q + .05n
4.4 = .2q
q = 22
22 of the coins are quarters.
Answer = p=12-4 -12=17=18+19
p-q
p=12
Answer:
176.39 inches or
14.70 feet
Step-by-step explanation:
Consider the right triangle made by Kristen, ground and shadow.
This triangle has one leg as 64 inches.
Next consider the right triangle formed by street light, ground upto shadow tip.
The two triangles have common angle of elevation and also another angle as 90 degrees.
Hence the two triangles would be similar
Also if A is the angle made by hypotenuse of both triangles with the ground we have

This value also equals by bigger triangle as

From these two we get
h = height of street light =
Answer:
-15
Step-by-step explanation:
-10+-9=-19+4=-15