model 6 operations of consecutive numbers (odd, even, square, etc.) Section-Wise Topic Notes With Detailed Explanation And Example Questions
MOST IMPORTANT quantitative aptitude - 6 EXERCISES
-
Basic Number System Aptitude Questions Practice Test with PDF »
-
Number System on Divisibility Multiple Add Subtract Live Test »
-
Top 255+ Number System Fraction Aptitude Questions Answers »
-
Top +299 Aptitude Number System (Find Unit Place) Mcq Quiz »
-
Top Number System Aptitude (Smallest Largest Fraction) MCQ »
-
199+ Aptitude Number System: Consecutive Numbers MCQ Quiz »
The following question based on number system topic of quantitative aptitude
(a) 1958
(b) 1598
(c) 1798
(d) 1978
The correct answers to the above question in:
Answer: (d)
Series of all natural numbers from 75 to 97 is in A.P. whose first term,
a = 75, last term, l = 97
If number of terms be n, then $a_n$ = a + (n–1)d
97 = 75 + (n – 1)
n = 97 – 74 = 23
$S_n = n/2(a+l)$
$S_23 = 23/2(75+97)$
= $23/2$× 172=1978
Practice number system (model 6 operations of consecutive numbers (odd, even, square, etc.)) Online Quiz
Discuss Form
Read more operations on consecutive numbers Based Quantitative Aptitude Questions and Answers
Question : 1
The sum of the squares of 3 consecutive positive numbers is 365. The sum of the numbers is
a) 36
b) 30
c) 33
d) 45
Answer »Answer: (c)
$10^2 + 11^2 + 12^2$ = 100 + 121 + 144 = 365
Required sum =10 + 11 + 12 = 33
Question : 2
The sum of the squares of three consecutive natural numbers is 2030. Then, what is the middle number?
a) 27
b) 25
c) 26
d) 28
Answer »Answer: (c)
Let the three consecutive natural numbers be x, x + 1 and x + 2.
According to question,
$x^2 + (x + 1)^2 + (x + 2)^2$ = 2030
or $x^2 + x^2 + 2x + 1 + x^2 + 4x + 4$ = 2030
or $3x^2 + 6x + 5 = 2030 $
or $3x^2 + 6x – 2025$ = 0
or $x^2 + 2x – 675$ = 0
or $x^2 + 27x – 25x – 675$ = 0
$x (x + 27) – 25 (x + 27)$ = 0
or $(x – 25) (x + 27)$ = 0
$x = 25 and – 27$
∴ Required number = $x$ + 1 = 25 + 1 = 26
Question : 3
The sum of all those prime numbers which are not greater than17 is
a) 41
b) 59
c) 58
d) 42
Answer »Answer: (c)
Prime numbers upto 17⇒ 2, 3, 5, 7, 11, 13, 17
Required sum = 2 + 3 + 5 + 7 + 11 + 13 + 17 = 58
Question : 4
The sum of first 20 odd natural numbers is equal to :
a) 400
b) 210
c) 300
d) 420
Answer »Answer: (a)
Series of first 20 odd natural numbers is an arithmetic progression with 1 as the first term and the common difference 2.
Sum of n terms in arithmetic progression is given by.
$S_n =1/2n[2a + (n – 1)d]$
Where a : First term; d : common difference
$S_{20}= 1/2×20[(2×1) + (20 -1) × 2]$
= 10 [2 + 38]=10 × 40 = 400
Note :Sum of first n consecutive odd numbers = $n^2$
Question : 5
The sum of all even numbers between 21 and 51 is
a) 560
b) 518
c) 540
d) 596
Answer »Answer: (c)
22 + 24 + 26 + ... + 50
= 2 (11 + 12 + 13 + .... + 25)
= 2 [(1 + 2 + 3 + ... + 25) – (1 + 2 + 3 ... + 10)]
= 2$({25×26}/2 - {10×11}/2)$
= 2 (325 – 55) = 2 × 270 = 540
Method 2 :
Sum of first n even numbers = n (n + 1)
Required sum = Sum of 25 even numbers from 1 to 50 – sum of 10 even numbers from 1 to 20
= 25×26 – 10 × 11 = 650 – 110 = 540
Question : 6
The sum of three consecutive odd natural numbers each divisible by 3 is 72. What is the largest among them?
a) 27
b) 21
c) 24
d) 36
Answer »Answer: (a)
Let the numbers be 3x, 3x + 3 and 3x + 6
3x + 3x + 3 + 3x + 6 = 72
9x + 9 = 72
9x = 72 – 9 = 63
x =$63/9$ = 7
∴ Largest number = 3x + 6 = 3 × 7 + 6 = 27
GET number system PRACTICE TEST EXERCISES
model 1 basic number system
model 2 divisibility, multiples, add and subtract based number system
model 3 fraction of numbers
model 4 finding unit place of a number
model 5 smallest and largest fraction/numbers
model 6 operations of consecutive numbers (odd, even, square, etc.)
number system Shortcuts and Techniques with Examples
-
model 1 basic number system
Defination & Shortcuts … -
model 2 divisibility, multiples, add and subtract based number system
Defination & Shortcuts … -
model 3 fraction of numbers
Defination & Shortcuts … -
model 4 finding unit place of a number
Defination & Shortcuts … -
model 5 smallest and largest fraction/numbers
Defination & Shortcuts … -
model 6 operations of consecutive numbers (odd, even, square, etc.)
Defination & Shortcuts …
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
Most Important Antonyms Vocabulary - IBPS Clerk Prelims 2024
Latest Antonyms multiple choice questions and answers with free PDFfor IBPS Clerk Prelims 2024. English Vocabulary practice exercise for all bank exam
Continue Reading »
Syllogism Practice Questions Answers PDF - IBPS Clerk 2024
Practice Verbal Reasoning Syllogism multiple choice questions and answers with Fully solved explanation, PDF for the IBPS Clerk Prelims 2024 Bank Exam
Continue Reading »
IBPS Clerk Prelims 2024 Synonyms Questions Solved Answers
Most important IBPS Clerk Prelims 2024 Synonyms and Antonyms multiple choice questions and answers with detailed solutions, English vocabulary PDF Download
Continue Reading »
New Cloze Test Questions and Answers PDF - IBPS Clerk 2024
The most important Cloze Test questions with detailed answers for upcoming IBPS Clerk prelims 2024. Latest English verbal ability practice MCQs, PDF
Continue Reading »