**Question: **The duration of telephone calls in certain city is measured by a random variable \(X\) with probability density

\[f(x)=0.5{{e}^{-0.5x}}\]

where \(x\) denotes the duration in minutes of a randomly selected call

**(a)** What percentage of the calls can be expected to last between 2 and 3 minutes?

**(b) **What percentage of the calls can be expected to last 2 minutes or less?

**(c) **What percentage of the calls can be expected to last more than 2 minutes

**Solution:**The solution consists of 114 words (1 page)

**Deliverables:**Word Document