150,327 views
1 vote
1 vote
How many five-digit odd numbers can be formed from the digits 1, 2, 3, 4,and 5 if no digit is repeated?

User Guilherme Viebig
by
2.9k points

2 Answers

20 votes
20 votes

Answer:

72

Explanation:

For a five-digit number to be odd it's one digit must be 1,3,5.

So there can be no repeats of any digits.

Let's look at numbers with one's digit being 1.

There are 4 ways to choose the tabs digit.

After that you can choose the hundreds digit 3 ways.

The thousands digit can then be chosen 2 ways.

Then finally the ten-thousands digit can be chosen 1 way.

4×3×2×1=24

24 odd numbers with one's digit being 1 that are 5 digits long only using 1,2,3,4, and 5 with no repeats.

That means there are 24 odd numbers with one's digit being 3 that are 5 digits long only using 1,2,3,4, and 5 with no repeats.

Also means there are 24 odd numbers with one's digit being 5 that are 5 digits long only using 1,2,3,4, and 5 with no repeats.

3(24)=72

User Steve Paulo
by
3.4k points
13 votes
13 votes

Answer:

10

Explanation:

the answer is 10 because there are only two odd numbers in here and the best. Even so when you put that in two digit odd number then it'll just be interchangeable those four numbers that aren't at the end of

User Mafonya
by
2.9k points