The answer is .3333 but I am still having the hardest time trying to figure it out...along with others here's the question and the table:
A study was recently done that emphasized the problem we all face with drinking and driving. Four hundred accidents that occurred on a Saturday night were analyzed. Two items noted were the number of vehicles involved and whether alcohol played a role in the accident. The numbers are shown below. Given that an accident involved 2 vehicles, what what is the probability that it involved alcohol?
................... NUMBER OF CARS INVOLVED
Alcohol? ----- 1------ 2 ------ 3 or more ------ TOTALS
Yes ----------- 54 ---- 97 ---------- 19 -------------- 170
No ------------- 20 ---172 --------- 38 -------------- 230
TOTALS ---- 74 --- 269 --------- 57 -------------- 400
Like I said earlier, the answer is .3333 out of the following choices:
A.) 0.4750
B.) 0.3290
C.) 0.3333
D.) 0.1118
I just don't know how they probability equals 0.3333. You would think it would be 97/269 = .3606
I've also tried P(2 car accident) = 269/400 = .6725 plus P(alchohol involved) = 170/400 = .425 minus P(2 car accident & alcohol involved) = 97/400 = .2425 therefore P(A) + P(B) - P(A & B) = .855 **now I know you would do this for P(A or B) provided that certain conditions are met but I tried it anyways because I was not coming up with .3333
Any ideas? I am 100% sure the table above is exactly the data used.
A study was recently done that emphasized the problem we all face with drinking and driving. Four hundred accidents that occurred on a Saturday night were analyzed. Two items noted were the number of vehicles involved and whether alcohol played a role in the accident. The numbers are shown below. Given that an accident involved 2 vehicles, what what is the probability that it involved alcohol?
................... NUMBER OF CARS INVOLVED
Alcohol? ----- 1------ 2 ------ 3 or more ------ TOTALS
Yes ----------- 54 ---- 97 ---------- 19 -------------- 170
No ------------- 20 ---172 --------- 38 -------------- 230
TOTALS ---- 74 --- 269 --------- 57 -------------- 400
Like I said earlier, the answer is .3333 out of the following choices:
A.) 0.4750
B.) 0.3290
C.) 0.3333
D.) 0.1118
I just don't know how they probability equals 0.3333. You would think it would be 97/269 = .3606
I've also tried P(2 car accident) = 269/400 = .6725 plus P(alchohol involved) = 170/400 = .425 minus P(2 car accident & alcohol involved) = 97/400 = .2425 therefore P(A) + P(B) - P(A & B) = .855 **now I know you would do this for P(A or B) provided that certain conditions are met but I tried it anyways because I was not coming up with .3333
Any ideas? I am 100% sure the table above is exactly the data used.
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97/269 = .3606 is correct
the answer options are incorrect
have confidence !
the answer options are incorrect
have confidence !