Of the 15-year-olds at a karate school, 9 have black belts and 15 have brown belts. among the 16-year-olds, 11 have black belts and 20 have brown belts. which age group has a higher ratio of black belts to brown belts?

The diameter of a circular chip is doubled to use in a new board game. the area of the new chip will be

Arefrigeration system at your company uses temperature sensors fixed to read celsius (°c) values, but the system operators in your control room understand only the fahrenheit scale. you have been asked to make a fahrenheit (°f) label for the high temperature alarm, which is set to ring whenever the system temperature rises above –10°c. what fahrenheit value should you write on the label

Afrequency table of grades has five classes (a, b, c, d, f) with frequencies of 3, 13, 14, 5, and 3 respectively. using percentages, what are the relative frequencies of the five classes?