2894
is it divisible by 13?
Remove the last number: 4
289.
Multiply 4 by 9. 9 x 4 = 36.
Subtract the number left from the last number multiplied by 4.
289 - 36
253 / 13
Therefore it isn't divisible by 13.
221
Last no: 1
1 x 9 = 9
Left no: 22
22 - 9
= 13
So 221 IS DIVISIBLE BY 13.
Or just simply divide the numbers.
