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Logic maths help

I got no idea how to start i was saying answer is French but then i see it can be Swiss, im lost
Help me out i got this from a text book. Sorry its so long

Karl’s favorite brownie recipe uses semisweet chocolate, very little
flour, and less than 1/4 cup sugar. He has four recipes: one French,
one Swiss, one German, and one American. Each of the four has
at least two of the qualities Karl wants in a brownie recipe. Exactly
three use very little flour, exactly three use semisweet chocolate,
and exactly three use less than 1/4 cup sugar.
The Swiss and the German recipes use different kinds of chocolate.
The American and the German recipes use the same amount of
flour, but different kinds of chocolate. The French and the American
recipes use the same amount of flour. The German and American
recipes do not both use less than 1/4 cup sugar.
Karl is very excited because one of these is his favorite recipe.
Which one is it?
Original post by bigmindedone
I got no idea how to start i was saying answer is French but then i see it can be Swiss, im lost
Help me out i got this from a text book. Sorry its so long

Karl’s favorite brownie recipe uses semisweet chocolate, very little
flour, and less than 1/4 cup sugar. He has four recipes: one French,
one Swiss, one German, and one American. Each of the four has
at least two of the qualities Karl wants in a brownie recipe. Exactly
three use very little flour, exactly three use semisweet chocolate,
and exactly three use less than 1/4 cup sugar.

The Swiss and the German recipes use different kinds of chocolate.
The American and the German recipes use the same amount of
flour, but different kinds of chocolate. The French and the American
recipes use the same amount of flour. The German and American
recipes do not both use less than 1/4 cup sugar.
Karl is very excited because one of these is his favorite recipe.
Which one is it?


I go with French.

If we do a Venn diagram (three overlapping sets: chocolate, sugar, flour), then the first part of the question (in red) tells us that there is exactly one recipe in each of the 4 regions arising from overlaps of the three sets.

We can now use the second part of the question to allocate the recipes - one to each region.
(edited 9 years ago)
Original post by ghostwalker
I go with French.

If we do a Venn diagram (three overlapping sets: chocolate, sugar, flour), then the first part of the question (in red) tells us that there is exactly one recipe in each of the 4 regions arising from overlaps of the three sets.

We can now use the second part of the question to allocate the recipes - one to each region.




Also i wanted to know if the question had a error because it says German and American recipies do not both have less than 1/4 cup of sugar but earlier it says atleast 3 uses less than 1/4 cup of sugar
Original post by bigmindedone
Also i wanted to know if the question had a error because it says German and American recipies do not both have less than 1/4 cup of sugar but earlier it says atleast 3 uses less than 1/4 cup of sugar


The question is correct, though it doesn't say "at least 3", it says "exactly 3"

Note "German and American recipies do not both have less than 1/4 cup of sugar" means at least one of German and American has more than 1/3 cup of sugar, NOT American do not have less... and German do not have less....
(edited 9 years ago)
Original post by ghostwalker
The question is correct, though it doesn't say "at least 3", it says "exactly 3"

Note "German and American recipies do not both have less than 1/4 cup of sugar" means at least one of German and American has more than 1/3 cup of sugar, NOT American do not have less... and German do not have less....


Thanks man this clarify everything for me
Original post by ghostwalker
The question is correct, though it doesn't say "at least 3", it says "exactly 3"

Note "German and American recipies do not both have less than 1/4 cup of sugar" means at least one of German and American has more than 1/3 cup of sugar, NOT American do not have less... and German do not have less....



Why couldnt it be Swiss
Original post by bigmindedone
Why couldnt it be Swiss


Post your working.

I used a table for the second part of the question of recipe against set overlap area.
(edited 9 years ago)

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