Help!!! probability?

Question

Each student is assigned a three- digit student ID. How many unique three- digit numbers can be created?

a) 30
b) 100
C) 300
d) 1000
e) 3000


Please help cant figure out!!!

Answer 1

There are 10 digits: 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9
You have 10 choices for the first number.
You have 10 choices for the second number.
You have 10 choices for the thrid number.
10*10*10 = 1000

Answer 2

I could give you the answer, but I also want to demonstrate how YOU can figure out the answer, whether it is a 3 digit number, or a 7-digit number.

Probability has to do with the chance that a certain event will happen among the group of all possible events.

Your question focuses on determining the group of all possible events, how many three-digit student ID's are available.

In this case, three choices are given: the choice for the first digit, the choice for the second digit, and the choice for the third digit.

If the numerals 1 2 3 4 5 6 7 8 9 and 0 are possible selections for each choice, then there are ten [10] possible selections for each choice.

10 selections times 10 selections times 10 selections gives you 1,000 choices, i.e., [that is] all the number combinations from 000 through 999.

Mathmatically this is shown as 10 * 10 * 10

Or reduced to 10^3 [ten to the third power]

If students were assigned a 4-digit number, then you would add that choice

10 * 10 * 10 * 10, or 10^4 [10,000 possible selections]

What if it is a 7-digit number?

[Answer that for yourself]

Here's the fun with probability!

What are the chances that you and your best friend will have sequential numbers, e.g. [for example] 345 & 346.

Your best friend is first in line and he gets to pick any number from the pile of 1000 numbers. The probability that he will pick any number is 1000 out of 1000, or 1.

What is the probability that you will pick a number which is sequentially next to your friends? [You get to pick second] There are 999 tiles left. The probability is 1 out of 999, or 1/999. [we are using as a rule in this example that 001 is sequential to 000 and that 000 is sequential to 999, otherwise it gets a little bit more complicated].

If you used letters instead of numerals?

26 letters * 26 letters * 26 letters, or 26^3, or 17,576

If you only use the letters a,b,c,d, and e?

5 letters * 5 letters * 5 letters, or 5^3, or 125

And if it were a 4-letter code using only the letters A through I

a b c d e f g h i = 9 letters

9 * 9 * 9 * 9, or 9^4, or 6,561

So, answer these questions...

How many telephone numbers in one area code?



How many license plate choices are there in Arkansas if there are 6 characters, the first three are letters, the last three are numbers? [An example plate would be ABC-123]




How many possible license plates if you live in California where there are seven characters and each character can be either a letters of the alphabet OR a number? [An example plate would be A9ZBRO2]










Answers:

Telephone numbers in one area code: 10^7, or 10,000,000

Arkansas license plates: 26^3 * 10^3, or 17,576,000

California license plates: 36^7, or 78,364,164,096 [that's 78 Billion plus]

Answer 3

If including 0-9 then the answer is as follows.

Three digit numbers means 3 spaces or ____ ____ ____

the first space you have numbers 0-9 (which are 10 options), then space 2 also has 0-9 (which are 10 options), and the same for space 3.

S0 you go: 10x10x10=1000

Note: 3 is not a number in the equation. You have three spaces and each space can have numbers any number from 0-9 (which is a choice of 10 numbers) space 2 and 3 are the same.

Answer 4

First digit (0 to 9) : 10 Possibilites
Second digit : Also 10
Third digit : Also 10

10 * 10 * 10 = 1000

ANSWER : D

Answer 5

10 in the first position, 10 in the second position and 10 in the third position. 10*10*10 or 1000
All the numbers from 000 to 999

Answer 6

Here's another way to look at it: 001 through 999 are 999 such numbers, plus 000 makes 1000.

Answer 7

It'll be D cuz.. 100-999 and anynumber less or more than 3 digits could be not count....

Answer 8

000,001, 002,.........,997,998,999 which is 1000 unique numbers

Answer 9

d

Answer 10

000 - 999

ANS : D.) 1000