Question
How many 4-digit numbers can be formed using digits 1 to
6 without repetition, such that the number is even?Solution
ATQ, Even number → last digit must be even → choices: 2, 4, 6 → 3 choices Remaining 3 digits from 5 others → 5 × 4 × 3 = 60 Total = 3 × 60 = 180
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