# Which one of the following could be the list of the students who work the second shifts at the gallery, in order from...

Jason on November 13, 2019

Video Explanation

Could we get a video walk through for this one?

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Irina on November 14, 2019

@JasonD,

The instructors do not have the ability to record videos, but I will forward your request to our curriculum team. If you have any specific questions or would like a written setup/ explanation in the meantime, let us know.

Thanks.

on March 14, 2020

A video walk through for this one would really help...

Ben on March 20, 2020

Unfortunately, while there is no video for this game at the moment, I would be happy to walk you through this game.

This is actually a very involved game with a lot of rule interactions and it really requires a strong understanding of when to split. Knowing when to make multiple game boards is a valuable skill that will spend your time upfront but then save it when you are working through questions. Let's look at how we can approach this.

We have five days with 2 shifts per day, first and second. For consistency, I will make first the top and second the bottom. I do this because I often make AM the top and PM the bottom in these types of games.

The diagram will look like this.

1st _ _ _ _ _
2nd _ _ _ _ _

M T W Th F

The rules are:

1) Nobody works twice on same day
2) L works two consecutive days on second shift (bottom)
3) G works first shift two times (top) but not consecutive
4) K works Tuesday and Friday
5) H and J work on the same day at least once
6) G and L never work on the same day

How many possible ways can L work twice consecutively during the second shift? 4 ways.

1st _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
2nd L L _ _ _ _ L L _ _ _ _ L L _ _ _ _ L L

Now we can place G in the first shift.

1st _ _ G _ G G _ _ _ _ _ _ _ _ G G _ G _ _
2nd L L _ _ _ _ L L _ _ _ _ L L _ _ _ _ L L

In the second and third diagrams, we do not know where the second G is to be placed. We do know however that J and H must be together in one day and that K must both Tuesday and Friday.

Looking at the last diagram. Placing K in Tuesday and Friday would preclude J and H from being together on at least one day. Therefore this isn't a valid scenario.

1st G K G _ G G K _ _ G _ G _ _ G
2nd L L _ _ F _ L L _ K _ K L L K

Now we can fill in the J/H togetherness.

1st _ K G J/H G G K _ J/H G H/J G _ _ G
2nd L L _ H/J F _ L L H/J K J/H K L L K

The remaining two spaces in each diagram is free to the remaining J and H.

I hope this helps. Please let me know if you have any other questions!