In a random survey of 3,015 boys age 11, the average height was 146 cm, and the standard deviation (SD) was 8 cm. A histogram suggested the heights were approximately normally distributed. Fill in the blanks. a. One boy was 170 cm tall. He was above average by SDs.
b. Another boy was 148 cm tall. He was above average by SDs.
c. A third boy was 1.5 SDs below the average height. He was cm tall.
d. If a boy was within 2.25 SDs of average height, the shortest he could have been is cm and the tallest is cm.
e. Here are the heights of four boys: 150 cm, 130 cm, 165 cm, 140 cm. Which description from the list below best fits each of the boys (a description can be used more than once)? Justify you answer
- Unusually short.
- About average
- Usually tall