Question

Estimate how many times a six-sided dice needs to be rolled to obtain the number 4 twenty times.

Twenty-four times
Sixty times
One hundred twenty times
Two hundred forty times

Answer 1

Given:

A dice is rolled.

To find:

How many times a six-sided dice needs to be rolled to obtain the number 4 twenty times.

Solution:

We know that, if we roll a dice then the possible outcomes are 1, 2, 3, 4, 5, 6.

Total possible outcomes = 6

So, the probability of getting a 4 in one roll is:

`P(4)=(1)/(6)`

Let n be the number of times the dice is rolled to obtain the number 4 twenty times. Then,

`(1)/(6)* n=20`

`(n)/(6)=20`

`n=20* 6`

`n=120`

Therefore, the correct option is C.