Question

What is the probability that a number selected from the numbers 1, 2, 3, ..., 15 is a multiple of 4?

Answer 1

\[\text{ There are 15 numbers from 1, 2, }\cdots, 15 . \]
\[\text{ Hence, the total number of cases is 15 } . \]
\[\text{ Again, the multiples of 4 are 4, 8 and 12 } . \]
\[\text{ Therefore, the total number of favourable cases is 3 }. \]
\[ \therefore P\left( \text{ the number is a multiple of } 4 \right) = \frac{\text{ Number of favourable cases }}{\text{ Total number of cases }} = \frac{3}{15} = \frac{1}{5}\]