Can anyone explain how to do this question?

Can anyone explain how to do this question?

For whatever reason (maybe I'm retarded) I'm just not following it.

While trick or treating in Clayton, NY (population 1,978), some friends play a counting game-they counted all the houses they visited while trick or treating (they all counted the same houses). Diego counted the houses by 5's, and had four houses left at the end. Madeline counted the houses by 7's, and had six houses left over at the end. Based on Diego's and Madeline's counts, how many houses did they visit? Is this the only possible answer? Explain why you are sure you found all possible counts.

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en.wikipedia.org/wiki/Chinese_remainder_theorem
twitter.com/AnonBabble

dedication

Yeah but I need some guidance.

Bump.

So far I have something like 5*x+4 = y
and 7*z+6=y

i'm not sure but maybe this??
en.wikipedia.org/wiki/Chinese_remainder_theorem

congruences
this is easy af I'm telling you

u do some ting 6mod7=x and then kill yourself

this question is retarded, you'll have to guess how many people live in a house on average, then it is solvable

multiple answers. you are on the right track.

It boils down to a linear system of equations with 2 equations and 3 unknowns and you already got them.

The only limitation is that x, z, y are natural numbers.

The amount of houses can be 34,69,104,139... etc.

Yeah that's what I thought. I appreciate the confirmation and further guidance. This question has been killing me.

Tell me more please.

So,

From what I got is X = (7Z+2)/5

That equals the two children's equations. I really have no idea how to pursue further like 7Z+2 part. How do I go about getting this broken down?

X is a natural number, hence 7z+2 is divisable by 5. Which means it must end in 0 or 5. Which means z is a multiple of seven ending in 8 or 3.

Ok you fucks:

X congruent 4 mod 5 => X = 5q + 4
X congruent 6 mod 7 => X = 7q + 6
Solve this linear system in integers for a solution that fits the population and you're golden

How does that not involve guesswork about how many people live in the house?

N mod 5 = 4 and N mod 7 = 6
The smallest N which satisfies both conditions is 34.
Modularies will remain the same whenever N increments by 35 (5 x 7)
So 69, 104, etc. are also possibilities.
Assume every house has at least 1 occupant.
1975 is a multiple of 5 but that would mean at least 1979 occupants, which is impossible. So 1944 is the largest number of doorbells they could have rung.

Literally where in the question are they asking you about the population of each house?
Point to it. I'll wait.

>34,69,104,139... etc.

do you think two kids are going to cover more than 34 houses in one night?

Doesn't appear explicitly..
But he asked "Explain why you are sure you found all possible counts."
The population puts an upper limit on the number of houses in town if we assume each house has at least 1 occupant.
Without that, the possibilities run into the billions.

Madeline and Diego are _really_ fast and _really_ gluttonous.

how the fuck should I know? we don't beg things from our neighbours at night once a year where I am from

X congruent 4 mod 5 => X = 5q + 4
X congruent 6 mod 7 => X = 7s + 6
*
5q-7s=2 which is a linear diophantine equation and then solve for s and q which fit the problem, which is actually an overly complicated way of doing this

the easiest would be to just say X = 5q + 4, X is an integer on this line, what number for X makes sense