There are three digits in your number ___ ___ ___
We sometimes refer to them as "slots"
The first slot is where the hundreds is placed.
For your number to be between 200 and 300 only the 2's could go in that slot
_ 2_ , ___, ___
Then there are 8 other numbers that could go in the next slot (since one of the two 2's is used up in the first slot), then 7 numbers left for the next slot
2 x8 x 7
Nine cards are numbered 1, 2, 2, 3, 3, 4, 6, 6, 6.Three of the nine cards are chosen and placed in a line, making a 3-digit number. Find how
many different numbers can be made in this way if the number is between 200 and 300.
2 answers
be sure to adjust for duplicate digits, since the equal digits are indistinguishable.