CBSE Class 10 Answered
2-the numer must be an even number
3-sum of digits must be divisible by 3
4-the number formed y the tens and units place must be divisible by 4
5- units place must be 0 or 5
11-take the sum of alternate digits. the difference of that sum is divisible by 1, then the num is divi by 11
e.g.
715
alt digits are 7,5 and 1
so 7+5=12
12-1=11 which is divi by 11 , hence 715 is divi by 11
for other nums take their factors if given num is divi by these factors, then, yes it'll be divi by the given number.e.g. for 6 you can chk if 2 and 3 are the factors of the given num, then the given num is divi by 6.
and so on.
for 7 you can subtract 2 times the last digit from the remaining part of the number.
e.g.
483
48-[2x 3]=42 which is divisible by 7 so, 483 is divi by 7
or
add 5 times the last digit two the remaining part of the num
48+[3 x 5]=63 which is divi y 7
if the hundreds digit is even examine the remaining part of the number whether it's divi by 7 or not
for 13-add 4 times the last digit to the rest and check
e.g.
533
53+[4 x3]=65 which is divi by 13, so given num is divi by 13