הסתברות — כיתה י"א · 4 יח"ל

פתרונות

1. $10$ — $\binom{5}{2}=\frac{5!}{2!\,(3)!}=10$.
2. $15$ — $\binom{6}{2}=\frac{6!}{2!\,(4)!}=15$.
3. $35$ — $\binom{7}{3}=\frac{7!}{3!\,(4)!}=35$.
4. $56$ — $\binom{8}{3}=\frac{8!}{3!\,(5)!}=56$.
5. $45$ — $\binom{10}{2}=\frac{10!}{2!\,(8)!}=45$.
6. $126$ — $\binom{9}{4}=\frac{9!}{4!\,(5)!}=126$.
7. $20$ — $\binom{6}{3}=\frac{6!}{3!\,(3)!}=20$.
8. $21$ — $\binom{7}{2}=\frac{7!}{2!\,(5)!}=21$.
9. $70$ — $\binom{8}{4}=\frac{8!}{4!\,(4)!}=70$.
10. $120$ — $\binom{10}{3}=\frac{10!}{3!\,(7)!}=120$.
11. $66$ — $\binom{12}{2}=\frac{12!}{2!\,(10)!}=66$.
12. $10$ — $\binom{5}{3}=\frac{5!}{3!\,(2)!}=10$.
13. $15$ — $\binom{6}{4}=\frac{6!}{4!\,(2)!}=15$.
14. $36$ — $\binom{9}{2}=\frac{9!}{2!\,(7)!}=36$.
15. $55$ — $\binom{11}{2}=\frac{11!}{2!\,(9)!}=55$.
16. $35$ — $\binom{7}{4}=\frac{7!}{4!\,(3)!}=35$.
17. $28$ — $\binom{8}{2}=\frac{8!}{2!\,(6)!}=28$.
18. $210$ — $\binom{10}{4}=\frac{10!}{4!\,(6)!}=210$.
19. $220$ — $\binom{12}{3}=\frac{12!}{3!\,(9)!}=220$.
20. $84$ — $\binom{9}{3}=\frac{9!}{3!\,(6)!}=84$.