Divisibility test for 2,3,4 and 5

By the end of this lesson, you should be able to;

  • Describe the divisibility test for 2, 3, 4 and 5.
  • State the multiples of some numbers
  • Test divisibility by 2, 3, 4 and 5.
    Divisibility test for 2
    Any number ending with an even digit i.e. ends with 0, 2, 4, 6, 8 is divisible by 2.
    Divisibility test for 3
    A number is exactly divisible by 3 if the sum of its digits is a multiple of 3.

Examples
144 = 1 + 4 + 4
= 9
Since 9 is a multiple of 3, then 144 is exactly divisible by 3.
Divisibility test for 4
A number is divisible by 4 if its last two digits are either zero or multiples of 4.
Example

image 10

179 36
36 ÷ 4 = 9
Since 36 is exactly divisible by 4 then 17936 is divisible by 4.

Divisibility test for 5
A number is divisible by 5 if it ends with 0 or 5 e.g. 365, 150, 255, etc.
Activity

  1. Choose by circling the numbers which are exactly divisible by 2.
    11, 13, 20, 26, 38, 47, 192, 4089, 998
  2. Test for divisibility by 3 and hence find out the numbers which are exactly divisible by 3.
    a) 37
    b) 123
    c) 333
    d) 12345
  3. Find and write only those numbers which are exactly divisible by 4

a) 3
b) 4
c) 90
d) 1441
e) 18254

  1. Write down the numbers divisible by 5 less than 60
  2. List the missing multiples of 5.
    170, , 180, , 190, 200, , 210, ___, 220