Homework: pg. 128 #10, 13 10.) A. (Verify the area=1) .20 C. .60 D . .50 E. 0.5 13.) A. Verify the area=1 B. 0.2 C. 0.6 D. 0.35 E.) The area between 0 and 0.2 is .35. The area between 0 and 0.4 is 0.6. The “equal areas” point is between 0.2 and 0.4.

Homework: pg. 131 #19, 20 19.) A. Erik did really well for his own times, but relatively slow compared to the other runners B. Erica was only relatively slower than usual by her own standards, but she was still pretty fast compared to the other swimmers at the state meet.

20.) A. 0.5(0.5)(0.8)+0.5(0.5)(0.8)+1(0.6)=1 Median=0.5; quartiles at 0.3 and 0.7 25.2% 49.6%

2.2 Normal Distributions

Normal Distributions

68-95-99.7 Rule The 68-95-99.7 Rule: Approximately 68% of the observations fall within of the Approximately 95% of the observations fall within of the Approximately 99.7% of the observations fall within of the

68-95-99.7 Rule

68-95-99.7 Rule

68-95-99.7 Rule IQ Test What % is above 115? What % is between 85 and 115? What % is between 70 and 85?

68-95-99.7 Rule B. Battery Life What % is at least 44 hours? How many of 1500 batteries are 1 s.d. within the mean? What % is between 45 and 54?

HW: pg 137 #25, 26