Problemas Resueltos - Razonamiento matemático
Problema 148
Se lanzan dos dados al azar y una sola vez. ¿Cuál es la probabilidad de obtener 7 puntos?
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\( \frac{2}{7} \)
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\( \frac{1}{7} \)
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\( \frac{4}{21} \)
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\( \frac{1}{6} \)
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\( \frac{1}{18} \)
Intenta resolverlo antes de ver la respuesta...
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\( \frac{1}{6} \)
El lanzamiento de dos dados, una sola vez, da los siguientes 36 posibles resultados:
| (1, 1) | (1, 2) | (1, 3) | (1, 4) | (1, 5) | (1, 6) |
| (2, 1) | (2, 2) | (2, 3) | (2, 4) | (2, 5) | (2, 6) |
| (3, 1) | (3, 2) | (3, 3) | (3, 4) | (3, 5) | (3, 6) |
| (4, 1) | (4, 2) | (4, 3) | (4, 4) | (4, 5) | (4, 6) |
| (5, 1) | (5, 2) | (5, 3) | (5, 4) | (5, 5) | (5, 6) |
| (6, 1) | (6, 2) | (6, 3) | (6, 4) | (6, 5) | (6, 6) |
| (1, 1) | (1, 2) | (1, 3) | (1, 4) | (1, 5) | (1, 6) |
| (2, 1) | (2, 2) | (2, 3) | (2, 4) | (2, 5) | (2, 6) |
| (3, 1) | (3, 2) | (3, 3) | (3, 4) | (3, 5) | (3, 6) |
| (4, 1) | (4, 2) | (4, 3) | (4, 4) | (4, 5) | (4, 6) |
| (5, 1) | (5, 2) | (5, 3) | (5, 4) | (5, 5) | (5, 6) |
| (6, 1) | (6, 2) | (6, 3) | (6, 4) | (6, 5) | (6, 6) |
De estas 36 posibilidades, 6 suman 7, que son:
| (1, 6) | (2, 5) | (3, 4) | (4, 3) | (5, 2) | (6, 1) |
| (1, 6) | (2, 5) | (3, 4) | (4, 3) | (5, 2) | (6, 1) |
Por lo tanto, la probabilidad de obtener 7 puntos es:
\[ \frac{6}{36} = \boldsymbol{ \frac{1}{6} } \]