Sandeep failed to troll

Probability Level 2

What is the non-negative remainder that you get when you divide integer x x by 3?

Sandeep posted the above question on Brilliant with a legitimate answer. Being naughty, he did not give away what the number x x was. Keeping in mind that there are three tries available for answering a question on Brilliant and assuming that you answer optimally, what is the probability that you correctly answered Sandeep's question?

1 2 \dfrac{1}{2} 1 0 Cannot be determined

Nihar Mahajan by Nihar Mahajan , 20, India

This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try refreshing the page, (b) enabling javascript if it is disabled on your browser and, finally, (c) loading the non-javascript version of this page . We're sorry about the hassle.

3 solutions

Hobart Pao
Apr 23, 2016

There are three possible remainders you can get when dividing by 3: 0, 1 or 2. It doesn't matter which number you start with. Even if you are the worst guesser, by the time you exhaust all the possible remainders, you will have gotten the question correct because the are three remainders you could have gotten and three tries, and one of those three is correct.

9 Helpful 0 Interesting 0 Brilliant 0 Confused
Abhay Tiwari
Apr 23, 2016

The remainder will be entered in atmost three tries so it is 100% probable that you will get the question right, only if you enter 0, 1 or 2, :p and thus you did the job to troll :)

1 Helpful 0 Interesting 0 Brilliant 0 Confused
No Kia
Apr 26, 2016

We all know that the possibilities are 0, 1 and 2. Wait, the options have 0 and 1. Which one? Well, if you know the divisibility rule for 3 (or another hint/rule/fact) you won't need to check the reminder because you know that it's 0. So it's more probable that you make a division by 3 when the reminder is 1 or 2. And that's the answer... 1.

0 Helpful 0 Interesting 0 Brilliant 0 Confused

0 pending reports

×

Problem Loading...

Note Loading...

Set Loading...