Prime Numbers part 2

Views:
 
Category: Entertainment
     
 

Presentation Description

No description available.

Comments

Presentation Transcript

“Act, Look, and Speak Like A Scholar” : 

Copyright © 2000 by Monica Yuskaitis “Act, Look, and Speak Like A Scholar”

Prime NumbersEratosthenes’ Sieve : 

Prime NumbersEratosthenes’ Sieve By Monica Yuskaitis Modified by Mr. Negron http://www.learnalberta.ca/content/me5l/html/math5.html

Eratosthenes(ehr-uh-TAHS-thuh-neez) : 

Copyright © 2000 by Monica Yuskaitis Eratosthenes(ehr-uh-TAHS-thuh-neez) Eratosthenes was the librarian at Alexandria, Egypt in 200 B.C. Note every book was a scroll.

Eratosthenes(ehr-uh-TAHS-thuh-neez) : 

Copyright © 2000 by Monica Yuskaitis Eratosthenes(ehr-uh-TAHS-thuh-neez) Eratosthenes was a Greek mathematician, astronomer, and geographer. He invented a method for finding prime numbers that is still used today. This method is called Eratosthenes’ Sieve.

Eratosthenes’ Sieve : 

Copyright © 2000 by Monica Yuskaitis Eratosthenes’ Sieve A sieve has holes in it and is used to filter out the juice. Eratosthenes’s sieve filters out numbers to find the prime numbers.

Definition : 

Copyright © 2000 by Monica Yuskaitis Definition Factor – a number that is multiplied by another to give a product. 7 x 8 = 56 Factors

Definition : 

Copyright © 2000 by Monica Yuskaitis Definition Factor – a number that divides evenly into another. 56 ÷ 8 = 7 Factor

Definition : 

Copyright © 2000 by Monica Yuskaitis Definition Prime Number – a number that has only two factors, itself and 1. 7 7 is prime because the only numbers that will divide into it evenly are 1 and 7.

Hundreds Chart : 

Copyright © 2000 by Monica Yuskaitis Hundreds Chart On graph paper, make a chart of the numbers from 1 to 100, with 10 numbers in each row.

Slide 10: 

Copyright © 2000 by Monica Yuskaitis Hundreds Chart

Slide 11: 

Copyright © 2000 by Monica Yuskaitis 1 – Cross out 1; it is not prime.

Hint For Next Step : 

Copyright © 2000 by Monica Yuskaitis Hint For Next Step Remember all numbers divisible by 2 are even numbers.

Slide 13: 

Copyright © 2000 by Monica Yuskaitis 2 – Leave 2; cross out multiples of 2

Hint For Next Step : 

Copyright © 2000 by Monica Yuskaitis Hint For Next Step To find multiples of 3, add the digits of a number; see if you can divide this number evenly by 3; then the number is a multiple of 3. 2 6 7 Total of digits = 15 3 divides evenly into 15 267 is a multiple of 3

Slide 15: 

Copyright © 2000 by Monica Yuskaitis 3– Leave 3; cross out multiples of 3

Slide 16: 

Copyright © 2000 by Monica Yuskaitis To find the multiples of 5 look for numbers that end with the digit 0 and 5. Hint For the Next Step 385 is a multiple of 5 & 890 is a multiple of 5 because the last digit ends with 0 or 5.

Slide 17: 

Copyright © 2000 by Monica Yuskaitis 4– Leave 5; cross out multiples of 5

Slide 18: 

Copyright © 2000 by Monica Yuskaitis 5– Leave 7; cross out multiples of 7

Slide 19: 

Copyright © 2000 by Monica Yuskaitis 6–Leave 11; cross out multiples of 11

Slide 20: 

Copyright © 2000 by Monica Yuskaitis All the numbers left are prime

The Prime Numbers from 1 to 100 are as follows: : 

Copyright © 2000 by Monica Yuskaitis The Prime Numbers from 1 to 100 are as follows: 2,3,5,7,11,13,17,19, 23,31,37,41,43,47, 53,59,61,67,71,73, 79,83,89,97

Credits : 

Copyright © 2000 by Monica Yuskaitis Credits Clipart from “Microsoft Clip Gallery” located on the Internet at http://cgl.microsoft.com/ clipgallerylive/default.asp