Remark
When ever you are asked a question like this one, the simplest answer is to find the rounded upper limit. Then go one number lower.Those are the two limits.
Solution
Use your calculator to get the exact answer. √7 = 2.64 roughly. Round up to get your first limit, even if it is closer to the lower limit. You always round up for the upper limit.
So far what you have is √7 < 3 Now subtract 1 from the 3.
2 < √7 < 3 Answer