+0  
 
0
119
3
avatar

How many even three-digit positive integers have the property that exactly two of the integer's digits are 6's?

 May 18, 2022
 #1
avatar+9461 
0

Suppose the first two digits are 6's.

 

The only possibilities are 660, 661, ..., 666, 667, ..., 669.

 

You can count the other possibilities by hand. Just make sure that you don't count 666 three times and 0 cannot be the first digit, and you're good to go.

 May 18, 2022
 #2
avatar
0

 

 

Although 661, 667, 669 are possibilities with regard to the 2-six requirement, they can't be 

part of the solution because the problem says "How many even three-digit positive integers"  

.

Guest May 18, 2022
 #3
avatar+9461 
0

Oh I missed "even". Thanks. But the counting method is still the same.

MaxWong  May 19, 2022

26 Online Users

avatar