305 is divisible by any of its factors, which are 1, 5, 61, and 305.
It really isn't worthwhile to find complicated divisibility rules for large numbers like 305 - because if there really is a divisibility rule, it will certainly be more complicated than just doing the division.Anyway, 305 = 5 x 61, so if a number is divisible by 305, it must be divisible by 5, and by 61. Divisibility by 5 is fairly simple; a number is divisible by 5 if it ends with 0 or 5. For divisibility by 61, see the following link; it looks fairly complicated.http://www.primepuzzles.net/puzzles/puzz_101.htmIt really isn't worthwhile to find complicated divisibility rules for large numbers like 305 - because if there really is a divisibility rule, it will certainly be more complicated than just doing the division.Anyway, 305 = 5 x 61, so if a number is divisible by 305, it must be divisible by 5, and by 61. Divisibility by 5 is fairly simple; a number is divisible by 5 if it ends with 0 or 5. For divisibility by 61, see the following link; it looks fairly complicated.http://www.primepuzzles.net/puzzles/puzz_101.htmIt really isn't worthwhile to find complicated divisibility rules for large numbers like 305 - because if there really is a divisibility rule, it will certainly be more complicated than just doing the division.Anyway, 305 = 5 x 61, so if a number is divisible by 305, it must be divisible by 5, and by 61. Divisibility by 5 is fairly simple; a number is divisible by 5 if it ends with 0 or 5. For divisibility by 61, see the following link; it looks fairly complicated.http://www.primepuzzles.net/puzzles/puzz_101.htmIt really isn't worthwhile to find complicated divisibility rules for large numbers like 305 - because if there really is a divisibility rule, it will certainly be more complicated than just doing the division.Anyway, 305 = 5 x 61, so if a number is divisible by 305, it must be divisible by 5, and by 61. Divisibility by 5 is fairly simple; a number is divisible by 5 if it ends with 0 or 5. For divisibility by 61, see the following link; it looks fairly complicated.http://www.primepuzzles.net/puzzles/puzz_101.htm
There are two ways of answering this.Check the number for divisibility by 2.Check the quotient for divisibility by 2.Check the quotient for divisibility by 2.Check the quotient for divisibility by 2.Check the quotient for divisibility by 2.Check the quotient for divisibility by 2.For large numbers, the check can be restricted to the number formed by the last six digits.
There is no easy rule for divisibility by 34.
The divisibility rule for 2 works because the base of our number system, 10, is divisible by 2.
It is not.
2 squared 1 = 4 so the divisibility rule is that it is divisible by 1, 2 and 4.
305 can only be [exactly] divided by 5 and not 2, 3, 6, 9 nor 10.Divisibility tests:2: NoNumber must be even (last digit divisible by 2). Last digit is 5 which is not even, so the whole number (305) not divisible by 2.3: NoAdd up the digits of the number; if this sum is divisible by 3, then the original number is divisible by 3: 3 + 0 + 5 = 8 which is not divisible by 3, so the original number (305) is not divisible by 3.5: YesLast digit is 0 or 5. Last digit is 5, so 305 is divisible by 5. 6: No6 = 2 x 3, so number must pass both tests for divisibility of 2 and 3; 305 fails tests for (both) 2 and 3 (above), so is not divisible by 6. 9: NoAdd up the digits of the number; if this sum is divisible by 9, then the original number is divisible by 9: 3 + 0 + 5 = 8 which is not divisible by 9, so the original number (305) is not divisible by 9.10: NoThe last digit of the number must be 0. Last digit is 5, so 305 is not divisible by 10.
The divisibility rule for 22 is that the number is divisible by 2 and by 11. Divisibility by 2 requires that the number ends in 0, 2, 4, 6 or 8. Divisibility by 11 requires that the difference between the sum of the the digits in odd positions and the sum of all the digits in even positions is 0 or divisible by 11.
12
305 - (42 +2) = 305 - 44 = 261
A divisibility rule is a statement of procedures to determine divisibility. For example:"A number is divisible by 2 if it ends with 0, 2, 4, 6 or 8".It does not make any sense to divide such a sentence by 2 or 895 or any other number!