Question
How many 5-digit even numbers can be formed using the
digits 0 to 9 if no digit is repeated?Solution
As per the question, To make an even 5-digit number using digits 0 to 9, the fifth box in the box should contain 0, 2, 4, 6, 8. Total such numbers=9P4×5 = 9×8×7×6×5 = 15120 Whereas in this number there is also a number with zero in the first position of the box, hence in this case we get a four-digit number, hence the total number of four digits. =8P3 ×4 =8x7x6x4 = 1344 Hence the five-digit even number = 15120-1344 =13776
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