1.0 KiB
1.0 KiB
id | title | challengeType | forumTopicId | dashedName |
---|---|---|---|---|
5900f4e01000cf542c50fff2 | Problem 371: Licence plates | 5 | 302033 | problem-371-licence-plates |
--description--
Oregon licence plates consist of three letters followed by a three digit number (each digit can be from [0...9]).
While driving to work Seth plays the following game:
Whenever the numbers of two licence plates seen on his trip add to 1000 that's a win.
E.g. MIC-012
and HAN-988
is a win and RYU-500
and SET-500
too (as long as he sees them in the same trip).
Find the expected number of plates he needs to see for a win. Give your answer rounded to 8 decimal places behind the decimal point.
Note: We assume that each licence plate seen is equally likely to have any three digit number on it.
--hints--
licensePlates()
should return 40.66368097
.
assert.strictEqual(licensePlates(), 40.66368097);
--seed--
--seed-contents--
function licensePlates() {
return true;
}
licensePlates();
--solutions--
// solution required