Practice Makes Perfect

Identify Prime and Composite Numbers

Some numbers, like (72), have actually many type of components. Other numbers, such as (7), have actually only two factors: (1) and also the number. A number through just two factors is called a prime number. A number through more than two components is called a composite number. The number (1) is neither prime nor composite. It has just one factor, itself.

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Definition: Prime Numbers and also Composite Numbers

A prime number is a counting number higher than (1) whose just determinants are (1) and itself.

A compowebsite number is a counting number that is not prime.


Figure (PageIndex5) lists the counting numbers from (2) via (20) together with their determinants. The highlighted numbers are prime, considering that each has actually only two determinants.

This number shows a table through twenty rows and also 3 columns. The first row is a header row. It labels the columns as “Number”, “Factor” and also “Prime or composite?” The second row lists the number 2, in red, under the “Number” column, the numbers 1 and 2 under the “Factors” column and the word prime under the “Prime or Composite?” column. The 3rd row lists the number 3, in red, under the “Number” column, the numbers 1 and 3 under the “Factors” column and also the word prime under the “Prime or Composite?” column. The fourth row lists the number 4 under the “Number” column, the numbers 1, 2 and also 4 under the “Factors” column and the word compowebsite under the “Prime or Composite?” column. The fifth row lists the number 5, in red, under the “Number” column, the numbers 1 and 5 under the “Factors” column and the word prime under the “Prime or Composite?” column. The 6th row lists the number 6 under the “Number” column, the numbers 1, 2, 3 and 6 under the “Factors” column and also the word compowebsite under the “Prime or Composite?” column. The seventh row lists the number 7, in red, under the “Number” column, the numbers 1 and also 7 under the “Factors” column and also the word prime under the “Prime or Composite?” column. The eighth row lists the number 8 under the “Number” column, the numbers 1, 2, 4 and 8 under the “Factors” column and the word compowebsite under the “Prime or Composite?” column. The nine row lists the number 9 under the “Number” column, the numbers 1, 3 and 9 under the “Factors” column and the word composite under the “Prime or Composite?” column. The tenth row lists the number 10 under the “Number” column, the numbers 1, 2, 5 and also 10 under the “Factors” column and also the word composite under the “Prime or Composite?” column. The eleventh row lists the number 11, in red, under the “Number” column, the numbers 1 and also 11 under the “Factors” column and also the word prime under the “Prime or Composite?” column. The twelfth row lists the number 12 under the “Number” column, the numbers 1, 2, 3, 4, 6 and also 12 under the “Factors” column and also the word composite under the “Prime or Composite?” column. The thirteenth row lists the number 13, in red, under the “Number” column, the numbers 1 and 13 under the “Factors” column and the word prime under the “Prime or Composite?” column. The fourteenth row lists the number 14 under the “Number” column, the numbers 1, 2, 7 and also 14 under the “Factors” column and also the word compowebsite under the “Prime or Composite?” column. The fifteenth row lists the number 15 under the “Number” column, the numbers 1, 2, 3, 5 and 15 under the “Factors” column and also the word composite under the “Prime or Composite?” column. The sixteenth row lists the number 16 under the “Number” column, the numbers 1, 2, 4, 8 and 16 under the “Factors” column and the word compowebsite under the “Prime or Composite?” column. The seventeenth row lists the number 17, in red, under the “Number” column, the numbers 1 and 17 under the “Factors” column and also the word prime under the “Prime or Composite?” column. The eighteenth row lists the number 18 under the “Number” column, the numbers 1, 2, 3, 6, 9 and 18 under the “Factors” column and also the word compowebsite under the “Prime or Composite?” column. The nineteenth row lists the number 19, in red, under the “Number” column, the numbers 1 and 19 under the “Factors” column and also the word prime under the “Prime or Composite?” column. The twentieth row lists the number 20 under the “Number” column, the numbers 1, 2, 4, 5, 10 and 20 under the “Factors” column and also the word composite under the “Prime or Composite?” column.2007 Lexus Es 350 Garage Door Opener Programming, Garage Door Opener

Weeks after graduation Total variety of dollars Frank put in the account Simplified Total
0 100 100
1 100 + 15 115
2 100 + 15 • 2 130
3 100 + 15 • 3
4 100 + 15 • <>
5 100 + <>
6
20
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Banking In March, Gina opened a Christmas club savings account at her financial institution. She deposited $75 to open up the account. Eincredibly week, she added $20 to the account. The table mirrors exactly how much money Gina had actually put in the account by the finish of each week. Complete the table by filling in the blanks. Weeks after opening the account Total variety of dollars Gina put in the account Simplified Total
0 75 75
1 75 + 20 95
2 75 + 20 • 2 115
3 75 + 20 • 3
4 75 + 20 • <>
5 75 + <>
6
20
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Writing Exercises

If a number is divisible by 2 and by 3, why is it likewise divisible by 6? What is the distinction in between prime numbers and also compowebsite numbers?