CLASS-4TEST OF DIVISIBILITY

TESTS OF DIVISIBILITY -

Divisibility means dividing a number leaving no remainder.

Ø  A number is said to be divisible by the numbers that divide it without leaving a remainder.

Ø  Divisibility tests help us to check whether a number is divisible by a given number or not.

DIVISIBILITY BY 2 :-

EXPLANATION :-

Ø  Make a table as shown in example and underline the digit in the one’s place .

Ø  If the underlined digit is 0, 2, 4, 6 or 8 , the given number is divisible by 2.

Example.1) Write whether the following numbers are divisible by 2 or not. Give reasons:

a. 7194            b. 84,029        c. 74,150

Ans.)  CHECK THE ONE’S DIGIT -> 0, 2, 4, 6, .bjn, 8

DIVISIBILITY BY 5 :-

EXPLANATION :

Ø  Make a table as shown in example and underline the digit in the one’s place .

Ø  If the underlined digit is 0 or 5, the given number is divisible by 5.

Example.1)  Write whether the following numbers are divisible by 5 or not. Give reasons:

a. 7,185         b. 24,028        c. 84,370

Ans:)  ( CHECK THE ONE’S DIGIT -> 0 or 5)

DIVISIBILITY BY 10 :-

EXPLANATION :

Ø  Make a table as shown in example and underline the digit in the one’s place .

Ø  If the underlined digit is 0 , the given number is divisible by 10.

Example.3) Write whether the following numbers are divisible by 10 or not. Give reasons.

a. 940         b. 78,648

Ans.)    (CHECK THE ONE’S DIGIT -> zero )

DIVISIBILITY BY 4 :-

EXPLANATION :

Ø  Make a table as shown in example and underline the digits in the ones and tens places (i.e. the last two digits) .

Ø  If the underlined last two digits can be divided by 4 leaving no remainder, the given number is divisible by 4.

Ø  OR, if the underlined last two digits are both zeroes (00), the given number is divisible by 4.

Example.4)  Write whether the following numbers are divisible by 4 or not. Give reasons.

a. 872        b. 6524       c. 70318        d.  5300

DIVISIBILITY BY 3 :-

EXPLANATION :

Ø  Make a table as shown in example and find the sum of the digits .

Ø  If the sum of the digits is divisible by 3, the given number is divisible by 3.

SOLVED EXAMPLES :-

Example.5) Write whether the following numbers are divisible by 3 or not. Give reasons:

a) 2,310               b) 84,028           c) 810