Question

The heights of kindergarten children are approximately normally distributed with the following. (Give your answers correct to four decimal places.) M = 47 and a = 3.6 inches (a) If an individual kindergarten child is selected at random, what is the probability that he or she has a height between 44.8 and 49.2 inches? (b) A classroom of 21 of these children is used as a sample. What is the probability that the class mean x is between 44.8 and 49.2 inches? (c) If an individual kindergarten child is selected at random, what is the probability that he or she is taller than 49.3 inches? (d) A classroom of 21 of these kindergarten children is used as a sample. What is the probability that the class mean x is greater than 49.3 inch

Answer 1

443-41 PC74.2) P/X-A 0 zo.6389 frem tandand barmal table -.338 P(X43) 0,2614 7 49.3-47 2.421 P(2z 2.927& P(Z2 2.4278 -0.9183 from standard nacmal table P4.3)000

lety Heig ht at Kinderaa rten childten fallaus namal disti buticn with PC44. 43.2) 48-43 3.6 44.2-47 -1 3.6 C44 84.2 f(-o.6111 06111 P(240.6111)- f(2-0.6111 0.7294-01 27 06 Fom standard narmal table PC44.24X44.2) 0.458g 49.2-47 9-61121 P44-8 4-2)448-11 3.6A2 61 P2.R005 22d005 P(2 28005)-(2-2.8005 to.9974-0.0026-Fan etaodard parmal table PC44 847443. 0.9949