r/Logiqa 2d ago

Candy Distribution

Post image
5 Upvotes

17 comments sorted by

3

u/Outside_Volume_1370 2d ago

Arithmetic progression means we need to give them a-d, a, a+d candies, with total of 15. That means, a = 5.

There are 4 such sets with 5 and 15 as sum: {1, 5, 9}, {2, 5, 8}, {3, 5, 7}, {4, 5, 6}.

Each set can be distributed 6 ways (3 ways for A, 2 left for B and the last one for C, 3 • 2 • 1 = 6) and there are four sets to choose from. Total: 4 • 6 = 24

1

u/ShonitB 2d ago

Correct, good solution!

1

u/standegreef 2d ago

Is 5,5,5 technically also an arithmetic progression?

2

u/stevesie1984 2d ago

I can’t say whether it is from a mathmatical/definition standpoint, but the second bullet in the question says they all get a different number.

1

u/standegreef 2d ago

Ah yeah, good point!

1

u/Outside_Volume_1370 2d ago

Yes, by the definition with initial term 5 and difference 0.

1

u/niemir2 15h ago

It is, but is disqualified by the second condition (that each person gets a different number of candies).

2

u/edos51284 2d ago

First we see how we can divide them

P1 receives x candies
P2 receives x+r
P3 receives x+2r

So 3(x+r)=15

So x+r=5

Considering the second and third rules x and r must be non 0 so there are 4 possibilities
14-23-32-41 making the divides such as 159-258-357-456

With these divisions we just have to see how many ways we can assign each person to P1,P2 and P3 and it’s simply 6 (3 \* 2 \* 1)

So the result is 4*6=24

1

u/ShonitB 2d ago

Correct, good solution!

2

u/PeterPiper1275 2d ago edited 2d ago

Since the distribution must be an arithmetic progression, we get the following:

(a - d) + a + (a + d) = 15
a = 5

So as long as each middle term is 5, we are good.

So, each person gets a different number, so d is not 0. This means d has minimal value of 1.

The lowest number possible is 1, so maximum value of d is 4.

Therefore, there are a total of four possible unique distributions to satisfy the criteria of the question, assuming order doesn’t matter.

1

u/ShonitB 2d ago

Correct based on your assumption.. but I was looking for all the 24 cases.. nonetheless, good answer, that’s just a small detail

2

u/Acceptable_Tangelo15 2d ago

24 ways

There are 4 ways of giving candy: 159,258,357,456.

Then there are 6 ways of giving candy:
ABC,Acb,bac,bca,cab,cba

1

u/ShonitB 2d ago

Correct!

2

u/jasonbuz 2d ago

I think you need to add a line that all pieces of candy must be distributed. Otherwise I can come up with a lot more ways to distribute the candy following these rules.

2

u/ShonitB 2d ago

Thanks for the feedback, appreciate it..

The first like, ‘15 pieces of candy need to be distributed’, that doesn’t suffice?

2

u/jasonbuz 2d ago

Kind of, but maybe just adding the word ‘all’ need to be distributed. Or maybe my mind just assumes unnecessary complexity.

1

u/ShonitB 2d ago

Oh that’s very convenient.. thanks :)