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.
--------
Question: Tim 's cat had kittens . He gave 3 to Jessica and 6 to Sara . He now has 9 kittens . How many kittens did he have to start with ?

Answer: 18


Question: Roden went to a pet shop . He bought 15 gold fish and 7 blue fish . How many fish did he buy ?

Answer: 22


Question: In fourth grade there were 8 students at the start of the year . During the year 5 students left and 8 new students came to school . How many students were in fourth grade at the end ?

Answer:
11