Problem: After eating a hearty meal they went to see the Buckingham palace. There, Rachel learned that 512 visitors came to the Buckingham palace that day. If there were 471 visitors the previous day and 808 visitors the day before that, how many visited the Buckingham palace within the past 89 days?
Solution: ( ( 512.0 + 471.0 ) + 808.0 ) = 1_791