A Maths Dictionary for Kids Quick Reference is a device friendly html version with definitions and detailed examples for over 950 math words and terms.
The statistics about the average cost of a haircut vary, but a few years ago American Salon, a publication for beauty industry professionals, reported the numbers as $21 for a cut in a salon with fewer than 6 chairs, and $44 for a salon with more than 13 chairs.
The price you pay for a haircut ultimately depends on how much you are willing to spend. If you consider paying more than $10 for a haircut absolutely ridiculous, then you probably won't ever set foot in a high-end salon that charges $100 for a cut.