Answer: There are 31 emails left in her inbox.
Explanation:
Since we have given that
Number of emails in her inbox = 78
Number of emails she deleted = 47
We need to find the number of emails that are left in her inbox.
So, for left we would use "Subtraction operator"
So, Number of emails left in her inbox = Number of emails in her inbox - Number of emails she deleted.
Hence, there are 31 emails left in her inbox.