Question

The number of 6 digit numbers that can be formed from 0 1 5 6 7 and 8 in which the first digit is not 0 are

Answer 1

Answer:

Lets see……you have given the digits 0, 1, 5, 6, 7, 8.

Step-by-step explanation:

Now you want to form today combinations possible using each digit, but the digits should only be 6 digit numbers.

That means that in each combination, digits can not be repeated.

Another condition is that the number should not begin with 0.

So what we have here is a total of 6 digits.

But excluding zero, we have 5 digits.

Total combinations possible using all 6 digits should be 6 X 5 = 30 combinations.

We have five less as the number should not begin with zero.

The correct answer is 30 combinations.

Answer 2

Answer:

5c1  5c1  4c1  3c1  2c1 1c1          hence 5*5*4*3*2*1=600

 _      _      _     _      _     _

Step-by-step explanation:

Since the first number can't be 0 so we can have 6-1=5 possibilities.

Now we need to taken one digit from the bunch which hasn't been used in first blank so 6-1=5 (now '0' is included.)

similarly,

3rd=> 5-1=4

4th=> 4-1=3

5th=> 3-1=2

6th=> 2-1=1

Hope it helps!