Find the probability that a two digit number formed by the digit 1, 2, 3, 4 and 5 is divisible by 4. -Maths 9th

1 Answer

Answer :

The two digit numbers can be formed by putting any of 5 digits at the one 's place and also one of the 5 digits at ten’s place. So, Total number of 2–digit numbers that can be formed using these 5–digits = 5 × 5 = 25 The 2–digit numbers formed by 1, 2, 3, 4 and 5 that are divisible by 4 are {12, 24, 32, 44, 52}, i.e, 5 in number. ∴ Required probability = \(rac{5}{25}\) = \(rac{1}{5}.\)

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