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10-23-2005, 03:43 PM
if the chances of A occuring is 70% and the chances of B occuring is 70%, what is the % that both will happen? and how do you come to your answer?

RiverTheNuts
10-23-2005, 03:47 PM
multiple probabilities just need to be multiplied, barring that the events are dependant on the other happening.

so 70% and 70% means both will happen 49% of the time, and neither will happen 9% of the time ( 30%*30%)
A not B will happen 70%*30% = 21%
B not A is the same

9+21+21+49 = 100, bingo

10-23-2005, 03:59 PM
so what is the % that 7 things will occur at once if they each have a 70% chance of occuring?
would you figure 70 to the 8th power? (and move decimal ? )

RiverTheNuts
10-23-2005, 04:24 PM
.7^7 for 7 things, yessir

You will see that this is a very low number, this is the reason that sports parlay bets never work /images/graemlins/frown.gif Picking 7 games right seems easy enough, but even if you pick at 70%, you will hardly ever win