Answer:
The reduction in probability of infection for an individual who wears both a mask and face shield is 68.4%
Step-by-step explanation:
Represent the event of wearing a Mask with M
Represent the event of wearing a face shield with F
[tex]P(M) = 95\%[/tex]
[tex]P(F) = 72\%[/tex]
Required
[tex]P(M\ and\ F)[/tex]
Since both events are independent;
[tex]P(M\ and\ F) = P(M) * P(F)[/tex]
Substitute values for P(M) and P(F)
[tex]P(M\ and\ F) = 95\% * 72\%[/tex]
Convert both percentages to fraction
[tex]P(M\ and\ F) = \frac{95}{100} * \frac{72}{100}[/tex]
[tex]P(M\ and\ F) = \frac{95 * 72}{100 * 100}[/tex]
[tex]P(M\ and\ F) = \frac{6840}{10000}[/tex]
[tex]P(M\ and\ F) = 0.684[/tex]
Convert to Percentage
[tex]P(M\ and\ F) = 68.4\%[/tex]