irrational number, any real number that cannot be expressed as the quotient of two integers.
Any number that can be written as a fraction with integers is called a rational number . For example, 17 and −34 are rational numbers. (Note that there is more than one way to write the same rational number as a ratio of integers.
1st Is rational
2nd one is irrational
3rd is irrational
4th is rational
13 ESSA É A RESPOSTA CORRETA DA SUA PERGUNTA.
Answer:
120
Step-by-step explanation:
solve for x then substitute
Answer:
0.55% probability that exactly 5 out of the first 13 customers buy a magazine
Step-by-step explanation:
For each customer, there are only two possible outcomes. Either they buy a magazine, or they do not. The probability of a customer buying a magazine is independent of other customers. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

In which
is the number of different combinations of x objects from a set of n elements, given by the following formula.

And p is the probability of X happening.
10% of his customers buy a magazine
This means that 
What is the probability that exactly 5 out of the first 13 customers buy a magazine?
This is P(X = 5) when n = 13. So


0.55% probability that exactly 5 out of the first 13 customers buy a magazine
Answer:
D 8 hours
Step-by-step explanation:
it has to be positive and it is obviously more than 1 hour so it has to be 8 hours by process of elimination.