2015 AMC 8 Problems/Problem 24: Difference between revisions
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<math>M=10</math> seems to work,until we realize this gives <math>N=12</math>, but <math>N>2M</math> so this will not work. | <math>M=10</math> seems to work,until we realize this gives <math>N=12</math>, but <math>N>2M</math> so this will not work. | ||
==Solution 2== | |||
<math>76=3N+4M > 10M</math>, giving <math>M \le 7</math>. | <math>76=3N+4M > 10M</math>, giving <math>M \le 7</math>. | ||
Since <math>M>4</math>, we have <math>M=5,6,7</math>. | Since <math>M>4</math>, we have <math>M=5,6,7</math>. | ||
Revision as of 11:50, 29 May 2019
A baseball league consists of two four-team divisions. Each team plays every other team in its division
games. Each team plays every team in the other division
games with
and
. Each team plays a 76 game schedule. How many games does a team play within its own division?
Solution 1
On one team they play
games in their division and
games in the other. This gives
Since
we start by trying
. This doesn't work because
is not divisible by
.
Next,
does not work because
is not divisible by
We try
this does work giving
and thus
games in their division.
seems to work,until we realize this gives
, but
so this will not work.
Solution 2
, giving
.
Since
, we have
.
Since
is
, we must have
equal to
, so
.
This gives
, as desired. The answer is
.
See Also
| 2015 AMC 8 (Problems • Answer Key • Resources) | ||
| Preceded by Problem 23 |
Followed by Problem 25 | |
| 1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 | ||
| All AJHSME/AMC 8 Problems and Solutions | ||
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