91. Which of the following is NOT a method of organizing raw data?
a) Random listing
b) Frequency distribution
c) Array
d) Grouped frequency distribution
Answer:
a) Random listing
Explanation:
Organizing data involves bringing structure to raw facts (like an array or frequency distribution). A “random listing” is, by definition, unorganized raw data.
92. The difference between the upper and lower class boundaries is called:
a) Class mark
b) Class width
c) Midpoint
d) Range
Answer:
b) Class width
Explanation:
In statistics, the class width (or class interval size) is found by subtracting the lower class boundary from the upper class boundary of that specific data class.
93. The mean of 5 numbers is 40. If one number, originally counted as 50, was incorrectly recorded as 30, what is the corrected mean?
a) 42
b) 44
c) 46
d) 48
Answer:
b) 44
Explanation:
The incorrect sum of the 5 numbers is 5 * 40 = 200. To find the correct sum, remove the incorrect number and add the correct one: 200 – 30 + 50 = 220. The corrected mean is 220 / 5 = 44.
94. The median of the first 10 prime numbers is:
a) 7
b) 10
c) 12
d) 13
Answer:
c) 12
Explanation:
The first 10 prime numbers are 2, 3, 5, 7, 11, 13, 17, 19, 23, 29. Since there is an even number of values, the median is the average of the 5th and 6th numbers: (11 + 13) / 2 = 24 / 2 = 12.
95. The mean weight of 5 students is 50 kg. If the weights of four students are 45, 55, 48, and 52 kg, the fifth student’s weight is:
a) 40 kg
b) 50 kg
c) 55 kg
d) 60 kg
Answer:
b) 50 kg
Explanation:
The total weight of all 5 students is 5 * 50 kg = 250 kg. The sum of the four known weights is 45 + 55 + 48 + 52 = 200 kg. The weight of the fifth student is 250 – 200 = 50 kg.
