## anonymous 5 years ago each digit 0,1,2,3,4,5,6,7,8, an 9 is writting on a slip of paper and the slips are placed in a hat. if 3 slips of paper are selected at ramdom find the probl that the 3 numbers are greater then 5

1. anonymous

3/10

2. anonymous

i mean 4/10

3. anonymous

No

4. anonymous

It's $\frac{4 \choose 3}{10 \choose 3}$

5. anonymous

there are ten choose 3 ways to choose three numbers out of ten ten choose 3 is 10*9*8/3/2=120 . This is your denominator. There are 4 choose 3 ways to choose the 4 of the ten numbers that are greater than 5. 4 choose 3 is 4. answer is 4/120 = 1/30

6. anonymous

Yeah, that's what I said ;p

7. anonymous

yup. couldn't find n choose k in the template.

8. anonymous

I always write equations manually. It's all just latex =) { n \choose k}

9. anonymous

much easier than using the editor

10. anonymous

thanks for the tip. {x\times y}$\frac{a}{b}$ just testing

11. anonymous

oops didnt work

12. anonymous

You have to be sure your equation is inside the $\ ] bits (no space) 13. anonymous \[x \times y$

14. anonymous

$\frac{a}{b}$

15. anonymous

damn

16. anonymous

$x\cdot y, \forall x \in N, f(g(x)) = (f\circ g)(x)$

17. anonymous

Hrm? you are making fractions?

18. anonymous

trying to typed $\frac{a}{b}$

19. anonymous

it's working for me.. (I can see a over b)

20. anonymous

it looks good in preview but doesn't post right

21. anonymous

i see no fraction bar!

22. anonymous

$x\times y$

23. anonymous

got one

24. anonymous

${n \choose k}$

25. anonymous

got it

26. anonymous

Sometimes the fraction bar doesn't show up for you when you post stuff. if you go to a different question and come back it can fix itself.