Question
How many two-digit even numbers can be formed using the
digits 3, 4, 5, 7, and 8, ensuring that no digit is repeated?Solution
Solution There will be two cases in which unit digit ends with an even number. In both cases, the number needs to end at either 4 or 8. In both cases, total count of remaining digits = 4 Therefore, total 2-digit number formed =Â 4C1Â XÂ 2CÂ1Â = 4 X 2 = 8
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