SOLUTION: How many 3-digit number can be formed from the digits 2,3,5,6,8 and 9 a) if repetition is not allowed? b) if repetition is allowed? c) how many digits in (a) are odd? d)how ma

Algebra.Com
Question 653761: How many 3-digit number can be formed from the digits 2,3,5,6,8 and 9
a) if repetition is not allowed?
b) if repetition is allowed?
c) how many digits in (a) are odd?
d)how many digits in (b) are greater than 500?
Answer by Edwin McCravy(20066)   (Show Source): You can put this solution on YOUR website!
How many 3-digit number can be formed from the digits 2,3,5,6,8 and 9
a) if repetition is not allowed?
Choose the 1st digit as any of the 6 digits.
Choose the 2nd digit any of the remaining 5 digits.
Choose the 3rd digit any of the remaining 4 digits.:

6󬊄 = 120

b) if repetition is allowed?
Choose the 1st digit as any of the 6 digits.
Choose the 2nd digit as any of the 6 digits.
Choose the 3rd digit as any of the 6 digits.:

6󬝲 = 216

c) how many digits in (a) are odd?
Choose the 3rd digit as 3,5, or 9.  That's 3 ways.
Choose the 1st digit any of the remaining 5 digits.
Choose the 2nd digit any of the remaining 4 digits.:

3󬊄 = 60

d)how many digits in (b) are greater than 500?
Choose the 1st digit as 5, 6, 8 or 9. That's 4 ways.
Choose the 2nd digit any of the 6 digits.
Choose the 3rd digit any of the 6 digits.:

4󬝲 = 144

Edwin
RELATED QUESTIONS

how many 3-digit numbers can be made with the digit 1,2,3,4,5,6,7 if repetition is... (answered by ikleyn)
How many different 4-digit even numbers can be formed from the digits 1,3,5,6,8, and 9 if (answered by ikleyn)
1. How many different 4-digit numbers can be formed from the digits 2, 3, 4, 5, 6, 7, and (answered by Alan3354)
Given the digits 4,5,6,7,8,how many 3 digit number can be formed if repetition is 1... (answered by ikleyn)
How many 4-digit odd numbers can be formed from the digits 1, 3, 5, 6, 8, and 9 if... (answered by math_helper)
How many 3-digit even numbers can be formed from the digits 1,2,6,8, and 9 if no... (answered by math_helper)
1. Consider the numbers 2, 3, 4, 5, 6, and 7. How many two-digit numbers can be formed... (answered by richard1234,richwmiller)
consider the numbers 2, 3, 5, 6 and 7. how many two digit numbers can be formed from... (answered by Edwin McCravy)
How many different two digit positive integers can be formed from the digits:0, 1, 2, 3, (answered by stanbon)
How many 3-digit odd numbers can be formed from the digits 1, 2, 4, 6, 8, 9 if repetition (answered by tommyt3rd)