Write the following in standard form: 603-8:2+ + 5.0 + 12.2^9.

A computer password consists of six characters.a. How many different passwords are possible if each character may be any lowerca

Citrus2011 [14]

Answer:

a) $6.04661760*10^8$

b) 0.27778

Step-by-step explanation:

a)

There are 26 lowercase letters and 10 digits.

The character that must be a digit can be generated in 10 different ways and the others, in 26+10=36 different ways.

Since the password is 6 characters long, by the Fundamental Rule of Counting there are

10*36*36*36*36*36 = 604,661,760

In scientific notation this number can be expressed as

$6.04661760*10^8$

b)

By the Fundamental Rule of Counting, there would be

$36^6$

different combinations of 6 characters, but only the number computed in a) are valid combinations, so the probability of generating a valid password is

$\displaystyle\frac{10*36^5}{36^6}=\displaystyle\frac{10}{36}=0.27778$

5 0

3 years ago

Assume that the number of watches produced every hour is normally distributed with a mean of 500 and a standard deviation of 100

horsena [70]

To evaluate the probability that in a randomly selected hour the number of watches produced is greater than 500 we proceed as follows:
z=(x-μ)/σ
where:
x=500
μ=500
σ=100
thus
z=(500-500)/200=0

Thus:
P(x>500)=1-P(x<500)=1-P(z<0)=1-0.5=0.5

Answer: 0.5~50%

8 0

3 years ago

Read 2 more answers

SAT reading and writing section scores of a random sample of twenty 11th-grade students in a certain high school are given below

kvasek [131]

Answer:

The value of test statistics is 25.

Step-by-step explanation:

We are given below the SAT reading and writing section scores of a random sample of twenty 11th-grade students in a certain high school;

380, 520, 480, 510, 560, 630, 670, 490, 500, 550, 400, 350, 440, 490, 620, 660, 700, 730, 740, 560

Let $\sigma$ = population standard of the reading and writing section SAT score of the students in this school

So, Null Hypothesis, $H_0$ : $\sigma \leq$ 100 {means that the reading and writing section SAT score of the students in this school is lesser than or equal to 100}

Alternate Hypothesis, $H_A$ : $\sigma$ > 100 {means that the reading and writing section SAT score of the students in this school is higher than 100}