Answer:
I think it's uhm twelve I'm not 100% sure though
Answer:
The percentage decrease is 15%.
Step-by-step explanation:
To find the percent decrease of any two numbers, subtract the numbers and divide it by the original.
So in this case:
20-17÷20
= 3÷20
= 0.15
Now convert to a percent.
0.15×100 = 15%
Answer:

Step-by-step explanation:
Use this formula,

where n is the amount of even intergers, a is the starting term, d is the common difference.
- the amount of even intergers from 2 to 200 is 100
- The starting number is 2
- The common difference is 2




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.