Question

Automated electron backscattered diffraction is now being used in the study of fracture phenomena. The following information is on misorientation angle (degrees).

Class: 0−<5 5−<10 10−<15 15−<20 20−<30 30−<40 40−<60 60−<90
Rel freq: 0.179 0.168 0.174 0.135 0.193 0.071 0.051 0.029
Is it true that more than 50% of the sampled angles are smaller than 15°, as asserted by researchers?
A. Yes, the proportion of sampled angles smaller than 15° is greater than 0.50.
B. Yes, the proportion of sampled angles smaller than 15° is not greater than 0.50.
C. No, the proportion of sampled angles smaller than 15° is greater than 0.50.
D. No, the proportion of sampled angles smaller than 15° is not greater than 0.50.

Answer 1

Answer: A. Yes, the proportion of sampled angles smaller than 15° is greater than 0.50.

Explanation:

Given the data :

Class: _______ relative frequency

0−<5 __________ 0.179

5−<10 __________ 0.168

10−<15 _________ 0.174

15−<20 _________ 0.135

20−<30 _________0.193

30−<40 _________ 0.071

40−<60 _________ 0.051

60−<90 _________ 0.029

Evaluating the proportion of sampled angles less than 15°. This consist of the following classes :

Class: ________frequency

0−<5 __________ 0.179

5−<10 __________ 0.168

10−<15 _________ 0.174

Summing up the relative frequency values :

(0.179 + 0.168 + 0.174) = 0.521

0.521 * 100% = 52.1%

Hence, more than 50% of the sampled angles are smaller than 15°