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.

Roadster 's Paving Company used 10 tons of cement to pave Lexi 's street and 5.1 tons of cement to pave Tess 's street . How much cement did Roadster 's Paving Company use in all ?
15.1

Fred has 40 baseball cards . Keith bought 22 of Fred 's baseball cards . How many baseball cards does Fred have now ?
18

Hoping to be named Salesperson of the Month , Rosa called the names from 10.2 pages of the phone book last week . This week , she called the people listed on another 8.6 pages of the same phone book . How many pages worth of people did Rosa call in all ?
18.8