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Re: How many 3 digit numbers can we make such that two of the digits are
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13 Jun 2021, 02:54
This is a selection problem
Let's select the two values of three which are going to be the same. This can be done in 3C2 ways
=> \(\frac{3!}{(2!*1!)}\) = 3 ways
Now the digit which is going to be the same can be selected in 9 ways
(we have digits from 1 to 9 to select as digits cannot be 0)
The digit which is different can be select in 8 ways. (all numbers from 1 to 9 except the one selected for the common digits)
So, in total we have 3 * 9 * 8 = 216 ways
So, answer will be D
Hope it helps!