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UCAT Medentry DM Question

Could someone explain?Screenshot (417).png
(edited 10 months ago)
Original post by charlotte05x
Could someone explain?Screenshot (417).png

You haven't show us the "following statements". (The attachment is for a different question.)
Reply 2
Original post by DataVenia
You haven't show us the "following statements". (The attachment is for a different question.)


Oh sorry! I'll attach it nowScreenshot (419).png!
Original post by charlotte05x
Oh sorry! I'll attach it nowScreenshot (419).png!

Great.

The first time I read through the conditions I was struck by the word "together", and tried to work out whether it was important or not. Having read it through a few times, I've concluded that what the question doesn't say (which it should) is that when the seven visitors arrive at the amusement park they split into two groups, some go on the Slide together and some go on the Drop together. So you can't get around some of the conditions which use the word "together" by having some people going on a particular ride and then having some other people go on that same ride later.

OK, now we've got that out of the way, I'm going to number the four conditions, just so they're easier to refer to in the explanation below.

(1) If the two men and one woman go on a ride together, both children must accompany them.
(2) If the three women go on one of the rides together, then none of the men can go on that ride.
(3) At least two of the seven visitors go one one ride and at least two go on the other.
(4) At least one man goes on the Slide.

We know that the three women don't go on the Slide, because condition (2) says that if they do then none of the men can go on it. But condition (4) says that at least one man does. As every person goes on exactly one ride, and we know all thee women don't go on the Slide, at least one of the women must go on the Drop. That is answer C.

We don't even need to check to see whether the other possible answers must be true or not because the question asks, "Which one of the following statements must be true?" So only one statement is true: C.
Reply 4
Original post by DataVenia
Great.

The first time I read through the conditions I was struck by the word "together", and tried to work out whether it was important or not. Having read it through a few times, I've concluded that what the question doesn't say (which it should) is that when the seven visitors arrive at the amusement park they split into two groups, some go on the Slide together and some go on the Drop together. So you can't get around some of the conditions which use the word "together" by having some people going on a particular ride and then having some other people go on that same ride later.

OK, now we've got that out of the way, I'm going to number the four conditions, just so they're easier to refer to in the explanation below.

(1) If the two men and one woman go on a ride together, both children must accompany them.
(2) If the three women go on one of the rides together, then none of the men can go on that ride.
(3) At least two of the seven visitors go one one ride and at least two go on the other.
(4) At least one man goes on the Slide.

We know that the three women don't go on the Slide, because condition (2) says that if they do then none of the men can go on it. But condition (4) says that at least one man does. As every person goes on exactly one ride, and we know all thee women don't go on the Slide, at least one of the women must go on the Drop. That is answer C.

We don't even need to check to see whether the other possible answers must be true or not because the question asks, "Which one of the following statements must be true?" So only one statement is true: C.

Thank you so much, your explanation makes so much sense :smile:

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