Question

Write the mobile numbers of 10 of your relatives and check if the
numbers are divisible by 2, 3, 5, 7 and 11. (By applying divisibility
rules)
Make a table of it.​

Answer 1

Divisibility Test for 2: The last digit is 0, 2, 4, 6, or 8.

Divisibility Test for 3: The sum of the digits is divisible by 3.

Divisibility Test for 5: The last digit is 0 or 5.

Divisibility Test for 7: Cross off last digit, double it and subtract. Repeat if you want. If new number is divisible by 7, the original number is divisible by 7.

Divisibility Test for 11: For a 3-digit number, sum of the outside digits minus the middle digit must be 0 or 11.