mads wrote:

A retirement plan for a company allows employees to invest in 10 different mutual funds. Six of the 10 funds grew by at least 10% over the last year. If Sam randomly selected 4 of the 10 funds, what is the probability that atleast 3 of Sam's 4 funds grew by at least 10% over the last year?

A. 6C3/10C4

B. 6C3.4C1/10C4

C. 6C3.4C1+6C4/10P4

D. 6P3.4P1/10C4

E. 6C3.4C1+6C4/10C4

Please explain your answer.

No of ways sam can select 4 funds = 10C4

no of ways he can select all 4 of those funds which grew by 10% =6C4

no of ways he can sleect 4 funds out of 3 of those funds which grew by 10% = 6C3*4C1

so probablity is = (6C3*4C1+6C4)/10C4

henc E is the answer

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My debrief: done-and-dusted-730-q49-v40