##################
### Module 8 Lab

## Download the "Real Property Taxes" Data from OpenBaltimore:
## https://data.baltimorecity.gov/Property/Real-Property-Taxes/27w9-urtv
## as a .csv file

# 1. Read the Property Tax data into R and call it the variable `tax`

# 2. How many addresses pay property taxes? 


###########
### This code will make the tax amounts numeric
# this is coming up in module 9
# check out `?gsub`
tax$cityTax = as.numeric(gsub("$","",tax$cityTax,fixed=TRUE))
tax$stateTax = as.numeric(gsub("$","",tax$stateTax,fixed=TRUE))
tax$amountDue = as.numeric(gsub("$","",tax$amountDue,fixed=TRUE))
##########

# 3. What is the total city and state tax paid?

# 4. What is the 75th percentile of city and state tax paid by ward?

# 5. Split the data by ward into a list: 

# Using `sapply()`
#	a. how many observations are in each ward?

#	b. what is the mean state tax per ward

#	c. what is the maximum amount still due?

# 6. Solve (5) using `table()` and `tapply()`