According to the meteorologist for the weekend, there is 60% probability of rain for Wednesday and 70% probability of rain for Thursday. What's the probability that:
a) it will only rain Wednesday
b) it will rain Wednesday or Thursday
c) it will rain both Wednesday and Thursday
d) it won't rain neither Wednesday or Thursday.
I've tried it several times using the formule but I get confused, should I add their percentage or not .. Please solve!
a) it will only rain Wednesday
b) it will rain Wednesday or Thursday
c) it will rain both Wednesday and Thursday
d) it won't rain neither Wednesday or Thursday.
I've tried it several times using the formule but I get confused, should I add their percentage or not .. Please solve!
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a. 60% X 30% = 18%
b. 100% - (40% X 30%) = 88%
c. 60% X 70% = 42%
d. 40% X 30% = 12%
b. 100% - (40% X 30%) = 88%
c. 60% X 70% = 42%
d. 40% X 30% = 12%
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just use the multiplicative principle !
a. P[WT'] = 0.6*0.3 = 0.18
b. P[W or T] = P[W] + P[T] - P[W & T] = 0.6+0.7- 0.6*0.7= 0.88
c. P[W & T] = 0.6*0.7 = 0.42
d.taking as "WILL rain neither.." P[W' & T'] = 1 - P[W or T] = 0.12
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a. P[WT'] = 0.6*0.3 = 0.18
b. P[W or T] = P[W] + P[T] - P[W & T] = 0.6+0.7- 0.6*0.7= 0.88
c. P[W & T] = 0.6*0.7 = 0.42
d.taking as "WILL rain neither.." P[W' & T'] = 1 - P[W or T] = 0.12
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