In Math Divisibility Rules is most commonly used to determine solutions in fastest way, by using few tricks and by remembering the divisibility rules.
A number is divisible by 2, if it is even or let us say it ends in 0, 2, 4, 6 or 8. Let us take an example, look at the number 512 and the number 431, here we are only concerned about the last digit or the digit in the ones place value. 512 ends in 2 which means it is even and therefore it is divisible by 2. However 431 ends in 1, which means it is not even or that is odd and it is not divisible by 2.
A number is divisible by 4, if their last two digits are divisible by 4. We take a look at 624 and 621, here we are only concerned with the last two digits, here the 2 and the 4 and in the next one it is 2 and the 1. Well 24 is divisible by 4. Therefore so is 624 is divisible by 4. But for our second number 621 here 21 the last two digit is not divisible by 4 so 621 is not divisible by 4. I have recently faced lot of problem while learning long division with decimals, But thank to online resources of math which helped me to learn myself easily on net.
Next we will look at the number 7, let us find out in few seconds if number is divisible by 7 or not? So divisibility rules 7 just indicates that number is divisible by 7 or not. First let us check the normal divisibility of a number. Let us have 6891, now to find out this number is divisible by 7 or not, we would start doing the long division and divide by 7. So 7 times 9 gives us 63, we get 5 as remainder with 9 as a carry. Again 7 times 8 is 56 so subtracting results into 3. 3 as a remainder carry 1 and 7 times 4 is 28 so the remainder is again 3. So here now we have 3 as a remainder this number 6891 is not divisible by 7.this was the long method of checking the divisibility rule. But there are few quicker rules as well. Our first step is to multiply the last digit by 2. Then subtract the remaining number from 2. Then, repeat the same process from the start till we get only two digits remaining. Then the last step would be check if the last two digits get divisible by 7.
Teaching divisibility rules is very easy because if the multiplication tables are memorized fully, then it becomes lot more simple to solve any question.
A number is divisible by 2, if it is even or let us say it ends in 0, 2, 4, 6 or 8. Let us take an example, look at the number 512 and the number 431, here we are only concerned about the last digit or the digit in the ones place value. 512 ends in 2 which means it is even and therefore it is divisible by 2. However 431 ends in 1, which means it is not even or that is odd and it is not divisible by 2.
A number is divisible by 4, if their last two digits are divisible by 4. We take a look at 624 and 621, here we are only concerned with the last two digits, here the 2 and the 4 and in the next one it is 2 and the 1. Well 24 is divisible by 4. Therefore so is 624 is divisible by 4. But for our second number 621 here 21 the last two digit is not divisible by 4 so 621 is not divisible by 4. I have recently faced lot of problem while learning long division with decimals, But thank to online resources of math which helped me to learn myself easily on net.
Next we will look at the number 7, let us find out in few seconds if number is divisible by 7 or not? So divisibility rules 7 just indicates that number is divisible by 7 or not. First let us check the normal divisibility of a number. Let us have 6891, now to find out this number is divisible by 7 or not, we would start doing the long division and divide by 7. So 7 times 9 gives us 63, we get 5 as remainder with 9 as a carry. Again 7 times 8 is 56 so subtracting results into 3. 3 as a remainder carry 1 and 7 times 4 is 28 so the remainder is again 3. So here now we have 3 as a remainder this number 6891 is not divisible by 7.this was the long method of checking the divisibility rule. But there are few quicker rules as well. Our first step is to multiply the last digit by 2. Then subtract the remaining number from 2. Then, repeat the same process from the start till we get only two digits remaining. Then the last step would be check if the last two digits get divisible by 7.
Teaching divisibility rules is very easy because if the multiplication tables are memorized fully, then it becomes lot more simple to solve any question.
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