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

[EX Q]: Sam has 86 yellow and 20 green marbles . Joan took 25 of Sam 's yellow marbles . How many yellow marbles does Sam now have ?
[EX A]: 61

[EX Q]: Sara had 4 quarters and 8 dimes in her bank . Her sister borrowed 4 dimes . How many dimes does Sara have now ?
[EX A]: 4

[EX Q]: An oil pipe in the sea broke . Before engineers started to fix the pipe , 2475 gallons of oil leaked into the water . A total of 6206 gallons of oil leaked before the pipe was fixed . How many gallons of oil leaked while the engineers were fixing the pipe ?
[EX A]:
3731