"Let's Make A Duel", known as "Quiz Duel!? VS Nazora Panel 9" in the Japanese version, is the eighty-first episode of the Yu-Gi-Oh! GX anime. It first aired in Japan on April 9, 2006, and in the United States on November 18, 2006.
Close to the end of the Duel, Bob activates "Quiz Panel Obelisk: 30" and Jaden recognizes the card. Bob realizes that was the card he dropped in front of Jaden earlier. Although Jaden at this point knew the entire answer to the question of the card, he ultimately chooses not to answer it completely because he considered it unfair for Bob and that since he knew the answer, it wouldn't be a challenge for him at all.
Jaden was mainly able to complete the problems of the cards matching his dormitory (though this is likely due to the Slifer questions being less about brains since it's the lowest dorm).
Although The Japanese anime feature all three Egyptian Gods on the "Quiz Panel" cards, the international version features only "Obelisk" in the three different colors.
Jaden guess that there are 50 monsters in "The Big March of Animals"'s artwork. Though Bob says he was close, there are actually 24 monsters (including the five unidentified monsters in shadow).
"Question" was first activated (onscreen) by Joey Wheeler in his duel against Yami Marik in episode 126 of the original series. Much like here, the monster in question is summoned due to the opponent having not seen the monster in the first place since it was discarded from the hand.
When Jaden destroys "Obelisk 10, Bob says "Time for your next question." This was the first one.
When Bob activates "Hunter Channel" to set off "Ra 20" he states that the damage would be 700 points when it is in fact 800. This is possibly due to the fact that both he and Jaden had 2700 points after taking an 800 point hit.
When Jaden doesn't answer "Obelisk 30" on purpose, Bob asks why since he could have won the duel. The damage that would have been inflicted from Jaden's right answer would not have won him the duel.