My Foggiest Moment

The thing I was having trouble with was finding the whole number in between a certain square root. I now understand it though. Ex. finding the whole number in between the square roots of 8 and 9. The numbers would be 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, and 80.