You are given a math word problem and you are supposed to apply addition or subtraction mathematical operators on the numbers embedded in the text to answer the following question and then only report the final numerical answer.

Example input: Last year , 90171 people were born in a country , and 16320 people immigrated to it . How many new people began living in the country last year ?
Example output: 106491
Example explanation: Total people living in the country = born - immigrated = 90171 - 16320 = 106491
Q: For Halloween Sarah received 66 pieces of candy from neighbors and 15 pieces from her older sister . If she only ate 9 pieces a day , how long would the candy last her ?
A:
9