Question:

The number of numbers between \(2000\) and \(5000\) that can be formed with the digits \(0,1,2,3,4\), repetition of digits not allowed, and are multiples of \(3\), is

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For divisibility by \(3\), first check the sum of digits. In digit-arrangement questions, decide the digit set first, then apply restrictions on the first digit.
Updated On: Jun 26, 2026
  • \(48\)
  • \(30\)
  • \(24\)
  • \(32\)
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The Correct Option is B

Solution and Explanation

Step 1: Identify the type of numbers required.
Numbers between \(2000\) and \(5000\) must be \(4\)-digit numbers.
Using digits \[ 0,1,2,3,4 \] without repetition, the thousand's digit can only be \[ 2,3,\text{ or }4 \]

Step 2: Use the divisibility rule of \(3\).
A number is divisible by \(3\) if the sum of its digits is divisible by \(3\).
We have to choose \(4\) digits from \[ 0,1,2,3,4 \] The sum of all five digits is \[ 0+1+2+3+4=10 \]

Step 3: Decide which digit is excluded.
A \(4\)-digit number will use \(4\) digits, so one digit is excluded.
If the excluded digit is \(r\), then the sum of selected digits is \[ 10-r \] For divisibility by \(3\), \[ 10-r \equiv 0 \pmod{3} \] Since \[ 10\equiv 1 \pmod{3}, \] we need \[ 1-r\equiv 0 \pmod{3} \] So, \[ r\equiv 1 \pmod{3} \] From the given digits, the possible excluded digits are \[ 1,4 \]

Step 4: Case 1, exclude \(1\).
The selected digits are \[ 0,2,3,4 \] All arrangements are \[ 4! \] But the thousand's digit cannot be \(0\).
Arrangements starting with \(0\) are \[ 3! \] Therefore, valid numbers are \[ 4!-3!=24-6=18 \]

Step 5: Case 2, exclude \(4\).
The selected digits are \[ 0,1,2,3 \] All arrangements are \[ 4! \] Arrangements starting with \(0\) are \[ 3! \] So, valid \(4\)-digit numbers are \[ 4!-3!=24-6=18 \] But the number must be between \(2000\) and \(5000\).
Among digits \(0,1,2,3\), the thousand's digit can be only \[ 2 \text{ or }3 \] For each fixed thousand's digit, the remaining \(3\) digits can be arranged in \[ 3! \] ways.
Thus, valid numbers are \[ 2\times 3!=2\times 6=12 \]

Step 6: Add both cases.
Total number of required numbers is \[ 18+12=30 \]

Step 7: Final conclusion.
Therefore, \[ \boxed{30} \]
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