# Which one of the following could be an accurate assignment of lab assistants to morning and afternoon sessions, respe...

abowers9594 on April 6, 2020

Video explanations

Are there supposed to be video explanations for this and the next two games? I can only see one for the last game.

Replies

BenMingov on April 12, 2020

Hi Abowers9594, thanks for writing.

Unfortunately, only the last game of test 66 has a video explanation as of now. If you have any questions regarding how to set these up for now, please message us through the boards and we will be sure to help!

AndreaK on April 12, 2020

Hi @abowers9594,

I can help with this one! Feel free to comment on the next two games if you would like help with those as well. On my end, I can only see the question you commented on here.

In this game, we have three days of the week (W, T, F), with both a morning and afternoon chemistry lab session (2 sessions per day) being held on each day (3 days). We’re distributing 6 lab assistants (J, K, L, N, O, R) into 6 sessions (two per day on the three days of the week), each session needing to be led by a different lab assistant. Because we have 6 sessions total and 6 lab assistants, we know each lab assistant will lead at least and at most one session.

Our setup could look something like this:

M A (Morning/Afternoon)
W _ _
T _ _
F _ _

Now let’s take a look at the rules.

1. This rule creates a horizontal block for our setup. On a piece of paper, I would draw a K and an R next to each other, a box around them (to signify the block) and a double prong arrow on top pointing to the K and the R on either side, indicating that they can switch places within the block. According to this rule both must be on the same weekday (hence the horizontal block), but either can be in the morning or afternoon (hence the arrows).

2. This rule creates something I call an impossible block. To indicate it, I would draw something similar to the above. I would draw L and O right next to each other, and draw a box around the two of them. However, from there I would draw an X through the box from corner to corner—indicating that this rule makes it impossible the have those two letters sides by side in my game board together.

3. I would indicate this rule something like this: _ N (As an extra reminder, I might also add a small subscript “A” beside and just below the N). Because our morning column is to the left and our afternoon column is to the right, this rule indicates how N might look in the game. It will be in the right column, next to another presently undetermined letter (hence the blank for the morning column spot in that weekday)

4. Because our days of the week are represented vertically on this setup, I would represent this rule by writing a J, a short line below the J, and then an O on the other side of the line. This indicates in a vertical format (so that it more closely represents how it will actually look in our setup) that J must come on a day before O (or in other words, J must come on the first or second day and O must come on the second or third day).

Given these rules, my first thought is that this is a good game for making scenarios. Because the first rule is a fairly restrictive block, I would start there making three scenarios.

M A
W K/R
T _ _
F _ _

M A
W _ _
T K/R
F _ _

M A
W _ _
T _ _
F K/R

(Note: Remember both K and R can be on either the morning or afternoon of their respective weekday, here represented by a slash instead of arrows as described above).

For the next three rules, let’s think about deductions. Notice Olivia is talked about more than once in the remaining rules. That’s a hint there are probably some deductions you can make about her!

Rule 2 says L can’t go with O. Rule 4 says J must go before O, so we know J cannot go on the same day as O either. We know K and R are already paired up. We have 6 lab assistants, and those four cannot go with Olivia. Therefore, there is only one remaining lab assistant that can go on the day Olivia goes, and that’s Nessa.

Rule 3 says Nessa must lead an afternoon session. So, we have another block!

l O N l

Nessa is on the right, since that’s the afternoon column.

Now that we’ve figured out O must go on the same day as N, we only have two remaining players without designated parters. Those are J and L. Therefore, they must go together on the same day too.

We now have three blocks, that look something like this.
l K/R l (either could be morning or afternoon)
l O N l (definitive on morning (left)/afternoon (right))
l J/L l (either could be morning or afternoon)

Finally, we also know that J must come on an earlier day than O. So, we know the
l ON l block must be below the J/L block on our game board.

With those deductions, we are left with three effective scenarios.

M A
W K/R
T J/L
F O N

M A
W J/L
T K/R
F O N

M A
W J/L
T O N
F K/R

As you can see, answer choice E matches our third scenario here. The rest of the answer choices break one of our rules.

Hope this helps you navigate the game better, @abowers9594! Feel free to follow up if you have anymore questions. Additionally, feel free to follow up if you have anymore questions about the other game you mentioned above.