Advertisements
Advertisements
प्रश्न
How many three-digit numbers are there with 3 in the unit place?
without repetition
Advertisements
उत्तर
The digits are 0, 1, 2, 3, 4, 5, 6, 7, 8, 9
A three-digit number has 3 digits 1’s, 10’s and 100’s place.
The unit place is (filled by 3) filled in one way.
After filling the unit place since the digit ‘0’ is there
We have to fill the 100’s place.
Now to fill the 100’s place we have 8 digits (excluding 0 and 3)
So 100’s place can be filled in 8 ways.
Now to fill the 10’s place we have again 8 digits (excluding 3 and any one of the number)
So 10’s place can be filled in 8 ways.
∴ Number of 3 digit numbers with ‘3’ in unit place = 8 × 8 × 1 = 64
APPEARS IN
संबंधित प्रश्न
How many two-letter words can be formed using letters from the word SPACE, when repetition of letters is not allowed?
How many numbers between 100 and 1000 have the digit 7 exactly once?
A teacher wants to select the class monitor in a class of 30 boys and 20 girls. In how many ways can the monitor be selected if the monitor must be a girl or a boy?
How many three-digit numbers can be formed from the digits 0, 1, 3, 5, 6 if repetitions of digits are not allowed?
How many two-digit numbers can be formed using 1, 2, 3, 4, 5 without repetition of digits?
Four children are running a race:
In how many different ways could they finish the race?
Count the number of three-digit numbers which can be formed from the digits 2, 4, 6, 8 if repetitions of digits is allowed
Count the numbers between 999 and 10000 subject to the condition that there are no restriction
Count the numbers between 999 and 10000 subject to the condition that there are at least one of the digits is repeated
How many three-digit numbers, which are divisible by 5, can be formed using the digits 0, 1, 2, 3, 4, 5 if repetition of digits are not allowed?
How many numbers are there between 1 and 1000 (both inclusive) which are divisible neither by 2 nor by 5?
Find the number of ways of distributing 12 distinct prizes to 10 students?
Find the value of `(12!)/(9! xx 3!)`
Find the value of `(("n" + 3)!)/(("n" + 1)!)`
Find the value of n if `1/(8!) + 1/(9!) = "n"/(10!)`
How many numbers are there between 99 and 1000 having atleast one of their digits 7?
The number of possible outcomes when a coin is tossed 6 times is ______.
The number of six-digit numbers, all digits of which are odd is ______.
