Question

An unbiased die with faces marked 1, 2, 3, 4, 5 and 6 is rolled four times. out of four face values obtained, the probability that the minimum face value is not less than 2 and the maximum face value is not greater than 5 is

Answer 1

total no. of combinations =
${6}^{4} = 1296$

any combinations having 1s or 6s are rejected

no. of combinations left =
$4 \times {6}^{3} = 864$
Probability = 864/1296 = 2/3