an exercise for dealing with data.

![i hate exercise][https://media.giphy.com/media/5qaaGRYtLv5JK/giphy.gif]

As a web developer you will mostly likely be taking in data from somewhere and most of the time the data coming in isn't formatted in the best way. This exercise is no different.

Before getting started take the time to look at the data you're given @ data/weather.json. The data is stored in an array of tuples (tuples tl;dr: a data structure which contains two values in a set).

Think about how you could transform this data to be easier to work with. You're given two functions to start with and encouraged to build more.

mean function accepts two arugments city and data and should return the average of rainfall for the city found in data.

variance function accepts two arugments city and data and should return the variance of rainfall for the city found in data.

How to calculate a mean value how to calculate standard deviation value