Instructions: 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.
Input: When Jake had 1 cat , he needed to serve 0.5 can of cat food each day . Now that Jake has adopted a second cat , he needs to serve a total of 0.9 can each day . How much extra food is needed to feed the second cat ?
Output:
0.4