Length of the model = 11.6 inch
Z-score for 30 = (30 - 25) / 5.8 = 0.8621
z-score for 20 = (20 - 25) / 5.8 = -0.8621
:
Note find probabilities from z-tables
:
Probability ( 20 < X < 30 ) = 0.8051 - 0.1949 = 0.6102
Answer:
D is not a supported statement
Step-by-step explanation:
Let take them one by one:
A: from table: 0.57; in statement: 0.5
0.57 > 0.5 so this is supported
B: from table: 0.2+0.16=0.36; in statement: 1/3=0.33,
0.36>0.33 so this is supported
C: 0.07 is the least, so this is supported
D: the table DOES NOT show number of students, but proportions. So statement '7 students' IS NOT supported
E: from table 0.20 overslept. 0.2 < 1/4=0.25, so this is supported