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Question
Count the number of three-digit numbers which can be formed from the digits 2, 4, 6, 8 if repetitions of digits is allowed
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Solution
Number of digits given = 4 (2, 4, 6, 8)
So the unit place can be filled in 4 ways,
10’s place can be filled in 4 ways and 100’s place can be filled in 4 ways
∴ The unit place, 10’s place and 100’s place together can be filled
(i.e) So the Number of 3 digit numbers = 4 × 4 × 4 = 64 ways
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