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.
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Question: There is 0.16666666666666666 cup of oil in Scarlett 's measuring cup . If Scarlett adds 0.6666666666666666 cup more , how much oil will be in the measuring cup ?

Answer: 0.8333333333333334


Question: There are 40 boys and some girls on the playground . There are 117 children altogether . How many girls are on the playground ?

Answer: 77


Question: It rained 0.9 inches on Monday . On Tuesday , it rained 0.7 inches less than on Monday . How much did it rain on Tuesday ?

Answer:
0.2