Basic Math Class (Number Part-II)
Numbers-II V. TESTS OF DIVISIBILITY 1. Divisibility By 2: A number is divisible by 2, if its unit's digit is any of 0, 2, 4, 6, 8 . Example. 84932 is divisible by 2, while 65935 is not. 2. Divisibility By 3: A number is divisible by 3, if the sum of its digits is divisible by 3. Example. 592482 is divisible by 3, since sum of its digits = (5 + 9 + 2 + 4 + 8 + 2) = 30, which is divisible by 3. But, 864329 is not divisible by 3, since sum of its digits =(8 + 6 + 4 + 3 + 2 + 9) = 32, which is not divisible by 3. 3. Divisibility By 4: A number is divisible by 4, if the number formed by the last two digits is divisible by 4. Example . 892648 is divisible by 4, since the number formed by the last two digits is 48, which is divisible by 4. But, 749282 is not divisible by 4, since the number formed by the last two digits is 82, which is not divisible by 4. 4. Divisibility By 5: A number is divisible by 5, if its unit's digi