Q13 of 54 Page 308

A two digit number is formed with the digits 3, 5 and 7. Find the probability that the number so formed is greater than 57 (repetition of digits is not allowed).

Since repletion of digits is not allowed, total no of numbers formed with 3,5 7 = 3×2 = 6


No of numbers greater than 57 = 1×2 = 2


⇒ probability



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