Answer: A microscope with a scale of 250:1 means that the object looked at will appear to be 250 times bigger.
Explanation:
Microscope are magnifying lenses used to view tiny things to make them bigger and more visible. The main function of a microscope is to magnify a tiny object or to magnify the little details of a larger object to examine minute specimens which the naked eye cannot see.
A microscope with a scale of 250:1 means that the object that is looked at will appear to be bigger by 250 times it's normal size.