Instructions: You are given a math word problem and you are supposed to apply multiple mathematical operators like addition, subtraction, multiplication, or division on the numbers embedded in the text to answer the following question and then only report the final numerical answer.
Input: there are some passengers on a bus . at a bus stop 7 more passengers got on the bus and 9 passengers got off . if there are 26 passengers in the bus in the end how many passengers were there at first ?
Output:
28