We must start by placing J in the fifth spot. If you look at the sequencing, this forces K into the 6th spot and G into the 7th spot. A, B, F, and D < J. K is the only letter with real latitude to move around, but since J is 5th, K must be 6th in order to fill the sixth spot. See figure below,

_, _, _, _, J, K, G.

From this we can see that the choice, K is third or K is fourth must be wrong.

At this point A and B must accomdate the restriction that FD is consecutive but in only four spaces.

The answer choice A is 2nd must be wrong. You should have drawn this from the previous problem (if you are taking the Practice Test). Every question you do, you learn something about the logic game, so use the previous information to your advantage.

The answer choice, B is third, if worked out, forces A to be in one of the first two spots, and therefore it must occupy the 1st spot. If it does, it splits the FD combination. So Byron cannot occupy spot 3.

A, F/D, B, F/D, J, K, G. The FD combination is split disobeying rule 4.

All that's left is Byron is spot 4. 

(F, D, A, B, J, K, G) or (A, F, D, B, J, K, G)

This problem is interesting in that it adds a new rule to the mix. This rule meshes with the existing rule, FD or DF, in a unique way. The new rule, distilled down, essentially means KD which combined with FD or DF forces KDF, in that specific order. DF is no longer variable, as K occupies F's alternate spot in front of D. 

Another effect of this is that K is no longer as free a variable. Because K is attached to D which is must be before J, J and G must occupy spots 6 and 7 respectively. 

Also, A must come before the "KDF combo" based on rule 3. This forces A into spot 1. Putting all this together, see below.

A, _, _, _, _, J, G.

This may seem like a lot of open spaces but because KDF is a combo and must stay in that specific order, there are only two possibilities: (A, B, KDF, J, G) and (A, KDF, B, J, G).

With these as our guidelines, we can begin to destroy answer choices and find that the only answer choice that can't be true that is K cannot occupy the fourth position. It can only occupy position 2 or 3.

If you combine the sequencing rules together, you'll find that the only real sequenced restrictions on F are the same as those of D and are restrcited as follows: D < J < G. A does not restrict FD in anyway. 

Since A doesn't not have to be first, but can be third, D can occupy any of the first 5 spots; therefore, as D and F are interchangeable, F can occupy any of the first 5 spots as well. So 5 is the correct answer. 

This problem restricts a current rule and introduces another. FD is now solidified in its order respective to the other and KJ is introduced. When trying to tackle this problem, looking at this as a situation with 5 positions helps,( _, _, _, _, _) with the variables being KJ, FD, G, A, B. This helps to simplify the sequencing.

The following rules apply in the new situation, A < B < KJ < G, and as well as FD < KJ. The last three spots are decided by the new rules (_, _, _, _, KJ, G). Applying FD < KJ allows for FD to be placed in front of A, in between A and B, and after B.

FD, A, B, KJ, G

A, FD, B KJ, G

A, B, FD, KJ, G

Since A and B must configure themselves one in front of the other, there are only three possible configurations - those listed above. 

The correct answer is (K, I, F, P, M, D). It does not disobey any of the spacing, sequencing rules, or stipulations set forth in the explanation of the scenario.

If you chose one of the incorrect answers, the reasons why they are wrong is explained below:

- (K, I, P, F, M, D) This violates rule 2, as K and F are seperated by more than 1 space.

- (F, D, K, P, M, I) This violates rule 3, the sequence that P comes before D or P < D.

- (I, P, K, D, F, M) This violates rule 1,  as I is separated from D by less than 3 spaces. 

- (M, D, K, M, F, I) This one does not specifically violate any of the rules but it does violate a stipulation set forth in the explanation that evert customer should get one wash only. M gets two washes and P recieves none. 

For this problem, you must work the whole situation through and apply all the rules.

Since, D=2, I=6. (I is fifth is incorrect)

Thus far: _, D, _, _, _, I

We then apply the rule P < D, and P must occupy spot 1. (P is fourth is incorrect)

Second step: P, D, _, _, _, I

Now we apply the F is separated by one space from K. Because of the limited space, F and K must occupy either spot 3 or 5. This does not disprove any answer.

Third Step: P, D, (F/K), _, (F/K), I

At this point, we have one more letter that can occupy a space, and due to the lack of extra space M MUST occupy position four; therefore, answer M is fourth is correct. 

Final Step: P, D, (F/K), M, (F/K), I

Note that F and K could potentially occupy either spot 3 or 5, but as the quetion asks what MUST be true, it is not neccesarily true that F occupy either 3 or 5, hence F is third is incorrect. Treat K similarly. 

This is another problem in which we must start by working through all the rules:

Since F is 5, K must be 3. It cannot occupy two spots after F as there is no seventh spot. See rule 2.

_, _, K, _, F, _

Therefore, the answer choice, P is 3 is a false statement.

If you apply rule 1, and look at the configuration thus far, you'll notice that I and D must occupy spots 2 and 6 exclusively in order to maintain a distance of 3 spots between them. 

_, (I/D), K, _, F, (I/D)

As this is the case, the statement M is 6 is false, I is 1 is false, and D is 1 is false. 

The only other answer choice that has not been proven false is P is 4. The sequence P < D can be obeyed by using the order as follows:

M, I, K, P, F, D

In this sequence, P < D is obeyed and P is 4. 

The trick to this question beyond the sequence is interpreting the quetion. "All of the following MUST be false EXCEPT", is the equivalent to a "what could be true" type question.  This type of question leaves latitude for the answer choices. The answer does not neccesarily have to be true; there merely needs to be one situation in which the answer could be true despite looking for a MUST be type of question. 

Following the whole process through, D is 2nd (_, D, _, _, _, _), "I" must follow in the 5th spot due to the new rule: (_, D, _, _, I, _).

P must come before D: (P, D, _, _, I, _)

F and K can only places with I in between: (P, D, _,(F/K), I, (F/K))

M can only be placed in one spot, 3rd (P, D, M, (F/K), I, (F/K))

The only answer choice that must be correct, is that M must be 3rd. All the others are false.

This is a problem that introduces new rules and restrictions: 

First, we'll start by placing the easy new restriction, M is 3rd.

(_, _, M, _, _, _)

The next step is to see how the new restriction I < K impacts the system. Considering both the sequence rules, I < K and P < D, in conjunction with the 3 spaces between I and D rule, we can extrapolate that I and D are no longer interchangeable. I must come before D. If we look at this the other way, (P, D, _, _, _, I, K) we'll notice that I and D are separated by appropriate distance, but that there are 7 spaces to be filled with only six vehicles. D cannot come before I. 

After this extrapolation, we must look at the orientation between F and K and how it impacts the placement of I and D. If we place I in the second spot, we wil have the following sequence: (_, I, M, _, _, D) we can see that there is no place for F and K to be placed without breaking the one space between F and K rule, so we must place I in the first spot: (I, _, M, _, D, _). This leaves room for F and K to be places with a space between in multiple orientations. 

The next step is to analyze how P < D will play a role. P can occupy one of two spots considering D's required position: 2 and 4. If we place P in spot four, we will have as follows: (I, _, M, P, D, _), but again, there will be no space for F and K to reside with only one space seperating them. So, we must place P in spot 2: (I, P, M, _, D, _).

At this point, finally, there are no more restrictions to account for. F and K are free to reside in either 4 or 6, while the other four are required to stay in their explained positions. (I, P, M, (F/K), D, (F/K)).

Now to answer the question: "Must be true except". I, P, M and D are required to be in specific spots, and therefore, as the answer choices correspond with their designated spots, they must be true. While F or K COULD be in spot 4 or 6, they don't have to be. This means it could not be true or could be false; therefore K is washed last is the correct answer, as it could be false.

This is an orienation question. The best approach is to go through the rules, and eliminate the answers that violate a rule. 

Rule 1 eliminates sequence D, H, E, A, G, B, F, C.

Rule 2 eliminates sequence H, A, E, F, D, C, G, B.

Rule 3 eliminates sequence E, H, A, G, C, F, D, B.

Rule 6 eliminates sequence E, H, A, G, D, F, C, B.

Sequence C, E, G, F, D, H, A, B is the only one that remains, therefore it is the correct answer.