I'm in 7th grade trying to take a pre-algebra class..... we just learned our rules but i have come to the conclusion of 133.
Total number of 3 digit numbers = 999-100+1(to include 100)= 900 numbers
Therefore numbers not divisble by 2,3,5 and 10 are
900*(1-1/2)*(1-1/3)*(1-1/4)*(1-1/5)*(1-1/10)= 216 numbers
this # is divisible by 3, 5, and 9 :-) ;-P
Well, darling, the positive integers divisible by 2 are all the even numbers, and the ones divisible by 3 are those multiples of 3. So, to find the numbers divisible by either 2 or 3, you just need to combine these two sets. In other words, it's the set of all even numbers and multiples of 3. Voilà!
Add together all the digits until you get a single figure answer. If that's divisible by three, so's the original number. E.g. 4,239 broken down to 4 + 2 + 3 + 9 = 18; 1 + 8 = 9, which is a multiple of 3. The original number is therefore divisible by 3
Out of that list, 255 is evenly divisible by 3 and 5.
'121'. 121/3 = 40.3333..... Not divisible. 121/5 any number that does not end in '5' or '0' is not divisible by '5' 121/7 = 17 3/7 Not divisible. 121/9 any number whose digits do not sum to nine is not divisible by '9' ; 1+2+1 = 4
Yes, the number 1720 is divisible by 3 because the sum of its digits (1 + 7 + 2 + 0) is equal to 10, which is divisible by 3.
All whole numbers are divisible by 1. Numbers are divisible by 2 if they end in 2, 4, 6, 8 or 0. Numbers are divisible by 3 if the sum of their digits is divisible by 3. Numbers are divisible by 4 if the last two digits of the number are divisible by 4. Numbers are divisible by 5 if the last digit of the number is either 5 or 0. Numbers are divisible by 6 if they are divisible by 2 and 3. Numbers are divisible by 9 if the sum of their digits is equal to 9 or a multiple of 9. Numbers are divisible by 10 if the last digit of the number is 0.
No. 189 is only evenly divisible by 3 and 9 (from the set provided). Using the following rules of divisibility on the number 189: Divisible by 2? No - the number is not even Divisible by 3? Yes - the sum of the digits (1 + 8 + 9 = 18) is divisible by 3 Divisible by 4? No - the last two digits are not evenly divisible by 4 Divisible by 5? No - the last digit is not a 0 or a 5 Divisible by 6? No - the number is not even Divisible by 9? Yes - the sum of the digits is divisible by 9 Divisible by 10? No - the number is not divisible by 2 or 5
If the number is even, it's divisible by 2. If the sum of the digits is a multiple of 3, the whole number is divisible by 3. If the last two digits are a multiple of 4, the whole number is divisible by 4. If the last digit is a 0 or a 5, the whole number is divisible by 5. If the number is even and divisible by 3, it's divisible by 6. If the sum of the digits is a multiple of 9, the whole number is divisible by 9. If the number ends in 0, it's divisible by 10.
3720 is even, so it is divisible by 2. The digits in 3720 add up to a multiple of 3, so it is divisible by 3. The units digit in 3720 is 0, so it is divisible by both 5 and 10. 3720 is divisible by both 2 and 3, so it is divisible by 6. The digits of 3720 do not add up to a multiple of 9, so it is NOT divisible by 9. Remember these tricks. Super useful. :)
2463. The trick is that a number is divisible by 3 if and only if the sum of its digits is divisible by 3. 1+3+2+4 = 10 (not divisible by 3), while 2+4+6+3 = 15 (divisible by 3).
Check the sum of the digits, if the sum divisible by 3 then the number is divisible by 3. Example 910: the sum of digits= 9 + 1 + 0 = 10, but 10 is not divisible by 3, so the number 910 is not divisible by 3. Example 2154: the sum of digits = 2 + 1 + 5 + 4 = 12, this sum is divisible by 3, so the number 2154 is divisible by 3. if the sum is long you can check the sum of the sum and apply the same rule. Example 52498731: the sum of digits = 5 + 2 + 4 + 9 + 8 + 7 + 3 + 1 = 39, the sum of the digits for 39 = 3 + 9 = 12, so the original number, i.e. 52498731 is divisible by 3.
To determine if 475 is divisible by 2, we check if it is an even number - it is not, so it is not divisible by 2. To check for divisibility by 3, we add the digits (4+7+5 = 16) and see if the sum is divisible by 3 - it is not, so 475 is not divisible by 3. For 5, we check if the last digit is 0 or 5 - it is not, so it is not divisible by 5. For 4, we look at the last two digits (75) and check if they form a number divisible by 4 - they do not, so 475 is not divisible by 4. Lastly, for 10, we check if it ends in 0 - it does not, so 475 is not divisible by 10.
If the number is even, it's divisible by 2. If the sum of the digits is a multiple of 3, the whole number is divisible by 3. If the last two digits are a multiple of 4, the whole number is divisible by 4. If the last digit is a 0 or a 5, the whole number is divisible by 5. If the number is even and divisible by 3, it's divisible by 6. If the sum of the digits is a multiple of 9, the whole number is divisible by 9. If the number ends in 0, it's divisible by 10.
No. 26 for instance the sum of the digits is 8 but not divisible by 4. 32 the sum of the digits is 5 but divisible by 4 The rules for some other numbers are 2 all even numbers are divisible by 2 3 The sum of the digits is divisible by 3 4 The last 2 numbers are divisible by 4 5 The number ends in a 0 or 5 6 The sum of the digits is divisible by 3 and is even 7 no easy method 8 The last 3 numbers are divisible by 8 9 The sum of the digits is divisible by 9
1- Any number is divisible by 1. 2- Any even number is divisible by 2. 3- If its digits add up to a number divisible by 3, the whole number is divisible by 3. 4- If the last two digits are divisible by 4, the whole number is divisible by 4. 5- If it ends in 5 or 0, the whole number is divisible by 5. 6- If it's even and also divisible by 3, the whole number is divisible by 6. 7- There is no rule for 7. 8- If the last three digits are divisible by 8, the whole number is divisible by 8. 9- If its digits add up to a number divisible by 9, the whole number is divisible by 9. 10- If it ends in 0, the whole number is divisible by 10.
Check your divisibility rules: 2: One's digit is an even number YES 3: The sum of the digits is divisible by 3 NO: 7 + 1 + 0 = 8 which is not divisible by 3 5: One's digit is a 5 or a 0 YES 9: The sum of the digits is divisible by 9 NO: 7 + 1 + 0 = 8 which is not divisible by 9 10: One's digit is a 0 YES