Katrina's mother is 2 inches shorter than her father, Katrina is 2 inches shorter than her mother, and Katrina's brother is 2 inches shorter than Katrina. Which best represents the change in height from Katrina's father to her brother?

a. - 8 inches

b. - 6 inches

c. 6 inches

d. 8 inches

The answer would be B. Let's say Katrina's father was 10 inches tall. Subtract 2 inches to measure Katrina's mother's height, subtract another 2 inches to measure Katrina's height. Finally, subtract another 2 inches to measure Katrina's brother's height. Add all the negative 2s together in order to get - 6. That is the difference between Katrina's father's height and her brother's height.