Thread: Need help with a question regarding darts...

A dartboard has two regions for earning points: 5 points and 7 points. What is the largest score that is impossible to earn?


I don't understand this question at all!

Originally Posted by help1

A dartboard has two regions for earning points: 5 points and 7 points. What is the largest score that is impossible to earn?


I don't understand this question at all!

you have to give us some constraints here. in theory, it is possible to earn an infinite amount of points if you played forever... in theory

Originally Posted by Jhevon

you have to give us some constraints here. in theory, it is possible to earn an infinite amount of points if you played forever... in theory

I have been searching around, and I think the general acceptance is 3 turns. Would that just be 20?

Originally Posted by help1

I have been searching around, and I think the general acceptance is 3 turns. Would that just be 20?

well, if you're a perfect shot, and you can hit the 7 point region all three times, then the largest score you can earn in 3 tries is 3(7) = 21

but that is too simple, i think there's something more fundamental missing from your question

Originally Posted by Jhevon

well, if you're a perfect shot, and you can hit the 7 point region all three times, then the largest score you can earn in 3 tries is 3(7) = 21

but that is too simple, i think there's something more fundamental missing from your question

21=7,7,7
20 - cannot be done with 3 darts

but I think that is not the question. I think we should be thinking what is the
largest number that cannot be writen in the form 7n+5m for some n,m in N.

RonL

Originally Posted by CaptainBlack

21=7,7,7
20 - cannot be done with 3 darts

but I think that is not the question. I think we should be thinking what is the
largest number that cannot be writen in the form 7n+5m for some n,m in N.

RonL

Oh .. forgot to say we have done these multiple times before (postage problems and similar), a search should turmn up the answer.

Like this one for example.

RonL

Scratch the 3 turns part. Its as many turns as you wish.

I think the answer is 23, but I want to have a way to actually solve it.