Exercise

# Summarizing the median life expectancy in 1957

Rather than summarizing the entire dataset, you may want to find the median life expectancy for only one particular year. In this case, you'll find the median in the year 1957.

Instructions

**100 XP**

- Filter for the year 1957, then use the
`median()`

function within a`summarize()`

to calculate the median life expectancy into a column called`medianLifeExp`

.