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.

Joan had 5 dimes in her bank . She spent 2 of her dimes . How many dimes does she have now ?
3

In 1 week , Mitch 's family drank 0.5 carton of regular milk and 0.1 carton of soy milk . How much milk did they drink in all ?
0.6

There are 48 erasers in the drawer and 30 erasers on the desk . Alyssa placed 39 erasers and 45 rulers on the desk . How many erasers are now there in total ?
117