+36916 If you want to know if it can EVENLY be divided by 7...you'll just have to divide it by 7 ...either in your head, on paper or with a calculator......if thee is NO REMAINDER , it is EVENLY divisible by 7 ......I do not know of any shortcuts like there is for 3
(If you add all of the numbers up and THEY are divisible by 3 then the number is too
Example: Is 513 divisible by 3? Add 5 + 1 + 3 = 9 9 is divisible by 3, so 513 is too)
+36916 If you want to know if it can EVENLY be divided by 7...you'll just have to divide it by 7 ...either in your head, on paper or with a calculator......if thee is NO REMAINDER , it is EVENLY divisible by 7 ......I do not know of any shortcuts like there is for 3
(If you add all of the numbers up and THEY are divisible by 3 then the number is too
Example: Is 513 divisible by 3? Add 5 + 1 + 3 = 9 9 is divisible by 3, so 513 is too)
To find out if a number is divisible by seven, take the last digit, double it, and subtract it from the rest of the number. If you get an answer divisible by 7 (including zero), then the original number is divisible by seven. If you don't know the new number's divisibility, you can apply the rule again.
Example: 329. Take the last digit which is 9, double it=18. Subtract 18 from 32=14, which is divisible by 7. Therefore 329 is divisible by 7. And you can repeat the rule over and over again.
