Statistics Model Questions Set 1 Section-Wise Topic Notes With Detailed Explanation And Example Questions
MOST IMPORTANT quantitative aptitude - 1 EXERCISES
The following question based on Statistics topic of quantitative aptitude
| Quality | Price per Pencil (in Rs.) | Money spent (in Rs.) |
| A | 1.00 | 50 |
| B | 1.50 | x |
| C | 2.00 | 20 |
(a) Rs. 30
(b) Rs.40
(c) Rs.10
(d) Rs.60
The correct answers to the above question in:
Answer: (a)
Number of Type A pencil = ${50}/1$ = 50
Number of Type B pencil = $x/{1.50}$
Number of Type C pencil = ${20}/2$ = 10
Average = ${\text"Total money spent"}/{\text"totalno.of pencil"}$ = 1.25
= ${x + 50 + 20}/{50 + 10 + {x/{1.50}}}$ = 1.25
= 70 + x = 1.25 $(60 + x/{1.50})$
70 + x = 75.00 + ${1.25}/{1.50}$x
x - ${125}/{150}$ x = 5
= ${25}/{150}$ x = 5
x = 30
Discuss Form
Read more model question set 1 Based Quantitative Aptitude Questions and Answers
Question : 1
The following table gives the frequency distribution of life length in hours of 100 electric bulbs having median life 20 h.
| Life of bulbs(in hours) | Number of bulbs |
| 8-13 | 7 |
| 13-18 | x |
| 18-23 | 40 |
| 23-28 | y |
| 28-33 | 10 |
| 33-38 | 2 |
a) 24
b) 14
c) 27
d) 11
Answer »Answer: (b)
Number of total bulbs = 100
∴ 7 + x + 40 + y + 10 + 2 = 100
⇒ x + y = 41 ... (i)
| Life of bulbs (in hours) | Number of bulbs | Cumulative Frequency |
| 8 - 13 | 7 | 7 |
| 13 - 18 | x | 7 + x |
| 18 - 23 | 40 | 47 + x |
| 23 - 28 | y | 47 + x + y |
| 28 - 33 | 10 | 57 + x + y |
| 33 - 38 | 2 | 59 + x + y |
| N = 100 |
The median life is 20 h, so median interval will be (18-23).
Here, l = 18, $N/2$ = 50
c = 7 + x, f = 40, h = 5
∴ Median = l + ${(N/2 - C)}/f$ × h
⇒ 20 = 18 + ${(50 – 7 – x)}/{40}$ × 5
⇒ 2 = ${50 – 7 – x}/8$
⇒ 16 = 50 – 7 – x
⇒ x = 43 – 16
⇒ x = 27
Missing frequency 'y' is 14.
Question : 2
What is the difference between the number of boys studying Mathematics and the number of girls studying Physics?
a) 30
b) 60
c) 20
d) 80
Answer »Answer: (a)
Difference in the number of boys studying Mathematics and Physics = 180 – 150 = 30
Question : 3
Read the following information carefully to answer the questions that follow. The average age of 6 persons living in a house is 23.5 years. Three of them are majors and their average age is 42 years. The difference in ages of the three minor children is same.What is the median of the ages of minor children?
a) 5 years
b) 7 years
c) 3 years
d) Cannot be determined
Answer »Answer: (a)
Total age of six persons = 23.5 × 6 = 141 years
Total age of three major persons = 42 × 3 = 126 years
∴ Total age of three minor children = 141 – 126 = 15 years
The difference in ages of the three minor children is same.
Therefore, we take ages may be:
5, 5, 5; 3, 5, 7; 2, 5, 8 and 1, 5, 9
In all the cases, median will be 5 years.
Median age of minor children = 5 years.
Question : 4
If each of n numbers xi = i (i = 1, 2, 3,..... n) is replaced by (i + 1) $x_i$ , then the new mean is
a) ${n(n + 1)}/2$
b) ${(n + 1)(n + 2)}/{3n}$
c) ${n + 3}/2$
d) ${(n + 1)(n + 2)}/3$
Answer »Answer: (d)
$(i + 1)x^i = (i + 1)x^i$ where i = 1, 2, 3, ------- n
$Σ↖{n}↙{i = 1}(i + 1)$ = 1.2 + 2.3 + 3.4 + 4.5 + -------meters
= $Σ↖{n}↙{n = 1} T_n$
= Σ n (n + 1)
= $Σn^2 + Σn$
= ${(n + 1)n(2n + 1)}/6 + {n(n + 1)}/2$
Mean = $1/n [{(n + 1) n (2n + 1)}/6 + {n(n + 1)}/2]$
= ${(n + 1)}/2 [{2n + 1}/3 + 1]$
= ${(n + 1)}/2 {(2n + 4)}/3$
= ${(n + 1)(n + 2)}/3$
So, option (d) is correct.
Question : 5
Which one among the following statements is not correct?
a) For average rate of increase when the rate of population growth is given, geometric mean is best suitable
b) For average rate of speed when different distances are covered by different rates of speed, harmonic mean is best suitable
c) For size of readymade garments, mode is the best suitable measure
d) For average level of intelligence of students in a class, arithmetic mean is the best suitable
Answer »Answer: (d)
Since, intelligence of students is an attribute, arithmetic mean is not suitable method.
Question : 6
What is the mode of the frequency distribution of SeriesII?
a) 36
b) 46
c) 26
d) 56
Answer »Answer: (b)
Mode of frequency distribution of series II is 46.
GET Statistics PRACTICE TEST EXERCISES
Statistics Model Questions Set 1
Statistics Shortcuts and Techniques with Examples
Verbal Reasoning
Question & Answer Quiz
Non Verbal Reasoning
Question & Answer Quiz
Quantitative Aptitude
Question & Answer Quiz
Computer MCQ
Question & Answer Quiz
General English
Question & Answer Quiz
History GK
Question & Answer Quiz
Polity GK
Question & Answer Quiz
Geography GK
Question & Answer Quiz
Economy GK
Question & Answer Quiz
General Awareness GK
Question & Answer Quiz
Recently Added Subject & Categories For All Competitive Exams
100+ Quadratic Equation Questions Answers PDF for Bank
Quadratic Equation multiple choice questions with detailed answers for IBPS RRB SO. more than 250 Attitude practice test exercises for all competitive exams
Continue Reading »
IBPS Aptitude Linear Equations MCQ Questions Answers PDF
Linear equations multiple choice questions with detailed answers for IBPS RRB SO. more than 250 Attitude practice test exercises for all competitive exams
Continue Reading »
New 100+ Compound Interest MCQ with Answers PDF for IBPS
Compound Interest verbal ability questions and answers solutions with PDF for IBPS RRB PO. Aptitude Objective MCQ Practice Exercises all competitive exams
Continue Reading »
100+ Mixture and Alligation MCQ Questions PDF for IBPS
Most importantly Mixture and Alligation multiple choice questions and answers with PDF for IBPS RRB PO. Aptitude MCQ Practice Exercises all Bank Exams
Continue Reading »