Question

how many numbers greater than 100 and divisible by 5 can be made from the digits 3 4 5 6 if no digit is repeated​

Answer 1

the numbers are 345 and 3465

the reason is the number should end with 5 to be divisible by 5

hope it helps u

Answer 2

Last number should be 5 since it should be divisible by 5.

Keeping that in mind, numbers greater than 100 using four numbers (3 4 5 6) can either be a 4 digit number or a 3 digit number.

So with 4 digits it can be _._._.5 where the first three digits can be 3 4 6 w/o repition.
The no. of possibilities for the first digit is 3 (3 4 6), the no. of possibilities for the second digit is 2 ( any two from 3 4 6 depending on which two were not considered as the first digit) and for the third digit, there is only one possibility (either 3or 4or 6)

So in an equation form, the total number of possibilities are 3 and 2 and 1 I.e. 3x2x1=6 possibilities

Do the same for a 3 digit number
_._.5

First digit possibilities = 3
Second digit possibilities = 2
Total no. of possibilities = 3x2=6

Therefore, the number can either be 3 digit no. OR a 4 digit no.

So total no of possibilities in 3 digits + total no. Of possibilities in 4 digits =6+6=12

Answer: 12 numbers can be made from digits 3 4 5 6 which are greater than 100 and divisible by 5 with no repitition