If John receives the same grade in economics and Italian, and if he fails Russian, which one of the following must be...

AndreaK April 11, 2020

Hi @ah3,

This is an odd game. Basically, that rule means that any two letter grades are considered consecutive if and only if they are adjacent (or next to) each other in the alphabet. So that means, for example, A and B could be considered consecutive. However, A and C could not be because A and C are not adjacent to each other in the alphabet.

Consecutive <—> adjacent

If and only if statements get double arrows, because the conditions are both sufficient and necessary to one another.

Let’s try this question together.

“If John receives the same grade in economics and Italian, AND if he fails Russian, which one of the following must be true?”

Let’s start with the second part of that stem’s premise. Failing Russian means that John received an E in Russian. We also know from rule 2 that his grades in Italian and Russian are consecutive. That means they are adjacent to one another in the alphabet. Because there is no grade lower than E, which John received in Russian, John then must have received a D in Italian (to be adjacent to E).

Now let’s take a look at the first part of that stem’s premise. John receives the same grade in economics and Italian. Because we know from what we deduced above that John receives a D in Italian, then we also know that John receives a D in economics.

Finally, we know from rule 3 that John receives a higher grade in economics than in history. Following from what we deduced above, we know that John has a D in economics. The only grade lower than D that John could have in history then is E.

That’s how we get to answer choice C, John has a E in history. Hope this helps! Feel free to let us know if you have anymore questions about this unusual game.

Salena October 2, 2020

This was a great explanation. I struggled with this set up as well. Thank you

July 29, 2021

Thank you this really helped!