Instruction 4-1
Mothers Against Drunk Driving Is a Very Visible

Instruction 4-1
Mothers Against Drunk Driving is a very visible group whose main focus is to educate the public about the harm caused by drunk drivers.A study was recently done that emphasised the problem we all face with drinking and driving.Four hundred accidents that occurred on a Saturday night were analysed.Two items noted were the number of vehicles involved and whether alcohol played a role in the accident.The numbers are shown below:
$$\begin{array} { | c | c | c | c | c | } \hline & { \text { Number of Vehicles involved } } & \\\hline \text { Did alcohol play a role? } & \mathbf { 1 } & \mathbf { 2 } & \mathbf { 3 } & \text { Totals } \\\hline \text { Yes } & 50 & 100 & 20 & 170 \\\hline \text { No } & 25 & 175 & 30 & 230 \\\hline \text { Totals } & 75 & 275 & 50 & 400 \\\hline\end{array}$$
-Referring to Instruction 4-1,given that 3 vehicles were involved,what proportion of accidents involved alcohol?

A) 20/170 or 11.77%
B) 20/50 or 40%
C) 20/400 or 5%
D) 20/30 or 66.67%