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.

Karen has 639 crayons . Cindy has 504 crayons . How many more crayons does Karen have than Cindy ?
135

Linda has 34 candies . Chloe has 28 . How many candies do they have in all ?
62

While on vacation , Haley took 50 pictures at the zoo and 8 at the museum . If she later deleted 38 of the pictures , how many pictures from her vacation did she still have ?

20