The propagation of fatigue cracks in various aircrafts parts has been the subjec
ID: 3111139 • Letter: T
Question
The propagation of fatigue cracks in various aircrafts parts has been the subject of extensive study in recent years. The accompanying data consists of propagation lives (flight hours/10^4) to reach a given crack size in fastener holes intended for use in military aircraft ("Statistical Crack Propagation in Fastener Holes Under Spectrum Loading." J. Aircraft, 1983: 1028-1032): 736 863 865 913 915 937 983 1.007 1.011 1.064 1.109 1.132 1.140 1.153 1.253 1.394 a. Compute and compare the values of the sample mean and median. b. By how much could the largest sample observation be decreased without affecting the value of the median? The histogram below shows the heights (in cm) distribution of 30 people. a) How many people have heights between 159.5 and 169.5 cm? b) How many people have heights less than 159.5 cm? c) How many people have heights more than 169.5 cm? d) What percentage of people has heights between 149.5 and 179.5 cm? The histogram below shows the level of cholesterol (in mg per dl) of 200 people. a) How many people have a level of cholesterol between 205 and 210 mg per dl? b) How many people have a level of cholesterol less than 205 mg per dl? c) What percentage of people has a level of cholesterol more than 215 mg per dl? d) How many people have a level of cholesterol between 205 and 220 mg per dl?Explanation / Answer
Soln 7:
a)
Mean = (0.736+0.863+0.865+0.913+0.915+0.937+1.007+1.011+1.064+1.109+1.132+1.14+1.153+1.253+1.394)/16 = 1.0296
Median = Mean of {N/2 and (N/2+1) term} = 1.009
Comparison of Mean and Median = 1.0296 - 1.009 =0.0206
b)By 1.394-1.011 = 0.383 (This much can be decreased without affecting Median
Ques 8 ) Data mentioned in plot is not clearly visible
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.