Answer
$P(none~of~the~3~has~driven~while~under~the~influence~of~alcohol)=0.357911$
Work Step by Step
$29$% $=0.29$
The event "21- to 25-year-olds has not driven while under the influence of alcohol" is the complement of "21- to 25-year-olds has driven while under the influence of alcohol". So, we use the Complement Rule (see page 275):
$P(21- to~25-year-olds~has~not~driven~while~under~the~influence~of~alcohol)=1-P(21- to~25-year-olds~has~driven~while~under~the~influence~of~alcohol)=1-0.29=0.71$
The events "21- to 25-year-olds 1 has not driven while under the influence of alcohol", "21- to 25-year-olds 2 has not driven while under the influence of alcohol" and "21- to 25-year-olds 3 has not driven while under the influence of alcohol" are independent.
Using the Multiplication Rule for Independent Events (page 282):
$P(none~of~the~3~has~driven~while~under~the~influence~of~alcohol)=P(21- to~25-year-olds~1~has~not~driven~while~under~the~influence~of~alcohol)\times P(21- to~25-year-olds~2~has~not~driven~while~under~the~influence~of~alcohol)\times P(21- to~25-year-olds~3~has~not~driven~while~under~the~influence~of~alcohol)=0.71\times0.71\times0.71=0.357911$
