Nothing Special   »   [go: up one dir, main page]
Scribd Logo
Upload

Welcome to Scribd!

  • 34 views

    Lesson - 16: Playing With Numbers About The Divisibility Rules

    Uploaded by

    Hamitha Begam
    This document discusses rules for determining if a number is divisible by certain other numbers without performing long division. It provides divisibility rules for numbers 2 through 11 and examples for each. Some key rules include: a number is divisible by 2 if the ones digit is even; divisible by 3 if the sum of the digits is divisible by 3; divisible by 4 if the last two digits are divisible by 4; and divisible by 5 if the ones digit is 0 or 5. It concludes with some practice problems applying these divisibility rules.

    Copyright:

    © All Rights Reserved
    Download as PPTX, PDF, TXT or read online from Scribd

    Lesson - 16: Playing With Numbers About The Divisibility Rules

    Uploaded by

    Hamitha Begam
    34 views15 pages
    This document discusses rules for determining if a number is divisible by certain other numbers without performing long division. It provides divisibility rules for numbers 2 through 11 and examples for each. Some key rules include: a number is divisible by 2 if the ones digit is even; divisible by 3 if the sum of the digits is divisible by 3; divisible by 4 if the last two digits are divisible by 4; and divisible by 5 if the ones digit is 0 or 5. It concludes with some practice problems applying these divisibility rules.

    Original Description:

    Original Title

    Divisibility rules

    Copyright

    © © All Rights Reserved

    Available Formats

    PPTX, PDF, TXT or read online from Scribd

    Did you find this document useful?

    Is this content inappropriate?

    This document discusses rules for determining if a number is divisible by certain other numbers without performing long division. It provides divisibility rules for numbers 2 through 11 and examples for each. Some key rules include: a number is divisible by 2 if the ones digit is even; divisible by 3 if the sum of the digits is divisible by 3; divisible by 4 if the last two digits are divisible by 4; and divisible by 5 if the ones digit is 0 or 5. It concludes with some practice problems applying these divisibility rules.

    Copyright:

    © All Rights Reserved
    Download as PPTX, PDF, TXT or read online from Scribd
    Download as pptx, pdf, or txt
    34 views15 pages

    Lesson - 16: Playing With Numbers About The Divisibility Rules

    Uploaded by

    Hamitha Begam
    This document discusses rules for determining if a number is divisible by certain other numbers without performing long division. It provides divisibility rules for numbers 2 through 11 and examples for each. Some key rules include: a number is divisible by 2 if the ones digit is even; divisible by 3 if the sum of the digits is divisible by 3; divisible by 4 if the last two digits are divisible by 4; and divisible by 5 if the ones digit is 0 or 5. It concludes with some practice problems applying these divisibility rules.

    Copyright:

    © All Rights Reserved
    Download as PPTX, PDF, TXT or read online from Scribd
    Download as pptx, pdf, or txt
    of 15

    LESSON - 16

    Playing with numbers


    About the divisibility rules :
    OBJECTIVE: TO,
    UNDERSTAND THE RULES OF
    DIVISIBILITY
    Definition:
    Divisibility: the ability to determine what numbers a larger number is
    divisible by evenly.

    There are some tricks that we can use to help us determine what
    numbers larger numbers are divisible by without doing long division.
    RULES OF DIVISIBILITY BY 2 :

    A number is divisible by 2 if the one’s digit is even.

    Therefore, any number that ends with 0, 2, 4, 6, or 8 is


    divisible by 2 evenly.
    Examples: 78; 102; 1,046; 6,550 .
    RULES OF DIVISIBILITY BY 3

    A number is divisible by 3 if the sum of the digits is a multiple


    of three.
    Example: Is 96 divisible by 3?
    Asn) In order to find out, we must add the digits
    9 + 6 = 15
    Is 15 a multiple of 3???
    YES, which means that 96 is divisible by 3.
    RULES OF DIVISIBILITY BY 4

    A number is divisible by 4 if the last two digits are divisible by


    four.
    Let’s take 124
    Example: The last two digits in 124 are 24
    Is 24 divisible by 4?
    Ans)YES, this means that 124 is divisible by 4!
    RULES OF DIVISIBILITY BY
    5
    A number is divisible by 5 if the one’s digit is 0 or 5.
    So, any number that ends with 0 or 5 is definitely divisible by 5!
    Examples: 10; 95; 115; 690; 4,615
    RULES OF DIVISIBILITY BY 6

    • A number is divisible by 6 if the sum of the digits is a multiple


    of three and even.
    • A number is also divisible by 6 if the number is divisible by
    both 2 and 3.
    804 is an even number
    8 + 0 + 4 = 12
    12 is a multiple of 3, which means that 804 is divisible by 6.
    RULES OF DIVISIBILITY BY 7
    A number is divisible by 7 :
    1) Take the last digit
    2) Double it
    3) Then subtract it from the rest of the number.
    Is this number a multiple of 7?
    Example: 203 . The last digit of 203 is 3
    Double 3, means 3 x 2 = 6
    Subtract 6 from 20 – 6 = 14
    Is 14 a multiple of 7??
    YES, which means that 203 is divisible by 7.
    RULES OF DIVISIBILITY BY 8

    A number is divisible by 8 if the last three digits are divisible by


    eight.
    Examples: 9,640 ÷ 8 = 80 so the whole number, 9,640, is
    divisible by 8
    184 ÷ 8 = 23 so,184 passes this divisibility test.
    It does not matter how big is the number,
    This trick will work on all numbers.
    RULES OF DIVISIBILITY BY 9

    A number is divisible by 9 if the sum of the digits is divisible by


    9.
    Example: 702
    Add the digits: 7 + 0 + 2 = 9
    Is 9 divisible by 9?
    YES, which means that 702 is also divisible by 9.
    RULES OF DIVISIBILITY BY 10

    A number is divisible by 10 if the last digit is 0.


    Like ,7620 ,
    Last digit is 0 , So its divisible by 10
    7620/10 = 762
    RULES OF DIVISIBILITY BY 11

    A number is divisible by 11 when the sum of the odd numbered


    digits is subtracted from the sum of even numbered digits and
    the result is divisible by 11
    Like, 5181913
    5+8+9+3=25 , 1+1+1=3
    25-3=22
    22/11=2
    So, 5181913 is divisible by 11
    EXTRA QUESTIONS
    1. Which of the following number is divisible by 2, 5 and 10?
    (I) 149
    (II) 19400
    (III) 720345

    2. Check whether the numbers are divisibility by 4


    (I) 23408
    (II) 100246
    (III)150126

    3. Which of the two nearest numbers to 19506 are divisible by 9?


    4. In each of the following numbers without doing actual division, determine whether the
    first number is divisible by the second number:
    (i) 17218; 6
    (ii) 11309634; 8
    (iii) 515712; 8

    5. 6 is a factor of 12066 and 49320. Is 6 a factor of 49320 + 12066 and 49320 - 12066? Yes
    or No

    6 . 9 is a factor of which number from the following?


    (i) 394683
    (ii) 1872546
    (iii) 5172354
    THANK YOU
    • Done by: Talha Abdul Ahad
    • Class: 8-C
    • Roll no.: 35

    You might also like