Question

A six-sided fair die is rolled 4 times in a row. The probability of getting a 4 only on the last trial is?

Answer 1

Answer with explanation:

When a die is rolled once, total favorable outcome ={1,2,3,4,5,6}

Probability of getting 4 on the die, when the die is rolled once

                         $=\frac{1}{6}$

Probability of not getting 4, when die is rolled once

             $=\frac{5}{6}$

Now, when the die is Rolled 4 times in a row,probability of getting a 4 only on the last trial is

         $=\frac{5}{6}\times \frac{5}{6} \times\frac{5}{6}\times\frac{1}{6}\\\\=\frac{125}{1296}$

                                         

Answer 2

 (5 /6)3 * ( 1/6) = 5^3 / 6^4. You can use a calculator or your computer to find out that the probability is 125/1296.  

I hope this was helpful!