Question

A dentist was making note of his upcoming appointments with different aged patients and the reasons for their visits. Regular cleaning Broken tooth 6 9 Patients under 18 years old 4. 1 Patients 19-60 years old What is the probability that a randomly selected appointment is with patients under 18 years old and is for a regular cleaning? Simplify any fractions.

Answer 1

The probability of selecting an appointment with patients under 18 years old is

$P=\frac{6+9}{6+4+9+1}=\frac{15}{20}=\frac{3}{4}$

Because there are 15 patients under 18 years old out of 20 patients in total.

The probability of regular cleaning appointments is

$P=\frac{6+4}{6+4+9+1}=\frac{10}{20}=\frac{1}{2}$

Because there are 10 regular cleaning appointments out of 20.

Then, we multiply both probabilities to find the answer

$P=\frac{3}{4}\cdot\frac{1}{2}=\frac{3}{8}$

Hence, the probability is 3/8.