ANSWER
You answered 56 phone calls.
EXPLANATION
The number of phone calls answered on Monday
[tex] = 15[/tex]
The number of phone calls answered on Tuesday
[tex] = 23[/tex]
The number of phone calls answered on Wednesday
[tex] = 18[/tex]
The number of phone calls answered on this week
[tex] = 15 +23 + 18 [/tex]
[tex] = 56[/tex]
