If a die is rolled twice, what is the probability that it will land on

Question

If a die is rolled twice, what is the probability that it will land on an even number at least once?

A. 1/4
B. 1/2
C. 3/4
D. 4/5
E. 5/6

Kinshook · Answer

Probability of landing on an even no at least once = 1 - probability of landing on odd number twice
= 1 - 3/6* 3/6 = 1 - 1/4 = 3/4

IMO C

Lampard42 · Answer

Since given "at least once" work with negative = 1 - prob of odd twice = 1-3/6*3/6 = 3/4 IMO C

Archit3110 · Answer

odd no ; 3/6*3/6 ; 1/4
atleast 1 even ; 1-1/4 ; 3/4
IMO C

CareerGeek · Answer

Prob (At least 1 even) = 1 - Prob(no even)
= 1 - Prob(2 odds)
= 1 - 3/6*3/6
= 1 - 1/4
= 3/4

IMO Option C

Pls Hit kudos if you like the solution

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BrushMyQuant · Answer

Given that a fair dice is rolled twice and We need to find what is the probability that it will land on an even number at least once?

As we are rolling two dice => Number of cases =  6^2  = 36

Let's solve the problem using two methods:

Method 1:

Now there are 4 outcomes possible
(Odd, Odd), (Odd, Even), (Even Odd), (Even, Even) and there is an equal chance of each of them happening

=>  P(At least one number is Even)  = P((Odd, Even) or (Even Odd) or (Even, Even)) =  \frac{3}{4}

Method 2:

Out of the 36 comes lets eliminate all options in which both the outcomes are odd
Both can be odd in 3*3 (=9 ways), as in the first roll we can get any number out of 1, 3, and 5. And in the second case also we have these 3 choices.

=>  P(At least one number is Even)  =  \frac{36 - 9}{36}  =  \frac{27}{36}  =  \frac{3}{4}

So,  Answer will be C 
Hope it helps!

Playlist on Solved Problems on Probability  here

Watch the following video to MASTER Dice Rolling Probability Problems

https://www.youtube.com/watch?v=5PVZYQXet18

bumpbot · Answer

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If a die is rolled twice, what is the probability that it will land on

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If a die is rolled twice, what is the probability that it will land on

Prep Toolkit

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