Reasoning

Number Systems and Series

143 Questions

Number systems and series questions assess the ability to manipulate numerical values and spot patterns. The focus includes digit arrangements, binary conversions, and identifying largest or smallest numbers. These reasoning tasks are common across major competitive examinations.

Digit manipulationLargest and smallest numbersBinary number systemsPositional numeral systemsNumber series ranking

Number Systems and Series Questions

Multiple choice maths numbers and place value forming numbers formation of greatest and smallest numbers identifying the largest and smallest numbers with given digits

Which of the following will be the last digit of the second highest number after the positions of the digits in each number is reversed? 

$738, 429, 156, 273, 894$.

  1. $1$
  2. $2$
  3. $4$
  4. $7$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
The given sequence is : $738,429,156,273,894$
After reversing the digits, the sequence becomes : $837, 924, 651, 372, 498$.
The second highest number is $837$ and it's last digit is $7$.
Hence, $7$ is the correct answer.
Multiple choice maths numbers and place value face value of digit large numbers general form of number

Study the following number sequence and answer the given question.
5 1 4 7 3 9 8 5 7 2 6 3 1 5 8 6 3 8 5 2 2 4 3 4 9 6
How many even numbers are there in the sequence which are immediately preceded by an odd number but immediately followed by an even number?

  1. 1

  2. 2

  3. 3

  4. 4
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In the given sequence there are 3 such combinations where an even number is immediately preceded by an odd number and immediately followed by even number.


5 1 4 7 3 9 8 5 7 2 6 3 1 5 8 6 3 8 5 2 2 4 3 4 9 6
Answer is Option $C$.

Multiple choice maths concepts of seven and eight digit numbers comparison of numbers comparing numbers operations on rational numbers indian place value chart largest and smallest numbers writing and expanding numbers

Arrange in ascending order:
$1,234; 2,345; 6,784; 1,543$

  1. $1,234; 2,345; 6,784; 1,543$
  2. $1,234; 1,543; 2,345; 6,784$
  3. $1,543; 1,234;2,345; 6,784$
  4. $1,543; 1,234; 6,784; 2,345$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Comparing digits at thousand's place followed by hundred's, ten's and one's place,


We can arrange the given numbers in ascending order as 
$1,234; 1,543; 2,345; 6,784$

Multiple choice maths concepts of seven and eight digit numbers comparison of numbers comparing numbers operations on rational numbers indian place value chart largest and smallest numbers writing and expanding numbers

If the digits of the number $5726489$ are arranged in ascending order, then how many digits will remain at the same position?

  1. None

  2. One

  3. Two

  4. Three
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The given number is $5726489$.


After arranging digits of number in ascending order the number becomes $2456789$

Now, we can see after arranging number in ascending order digits $6,8$ and $9$ remain at the same position.

$\therefore$  $3$ digits will  remain at the same position.

Multiple choice maths concepts of seven and eight digit numbers comparison of numbers comparing numbers operations on rational numbers indian place value chart largest and smallest numbers writing and expanding numbers

If the following numbers  are arranged in ascending order, what will be the middle number?
$687,\ 789,\ 648,\ 693,\ 672$

  1. 687

  2. 789

  3. 693

  4. 672
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Given numbers in ascending order is, 


$648, 672, 687, 693, 789$


It can be clearly seen that middle number is $687.$ 

Multiple choice maths numbers in indian and international systems indian system of numeration numbers to 1 million formation of large numbers

Which of the following statements is INCORRECT?

  1. The place value of the digit $3$ in the number $543765$ is $3000$
  2. The place value of the digit $6$ in the number $6734581$ is predecessor of $5999999$
  3. In the number $1876523$, the place value of the digit $1$ is $1000000$
  4. The place value of the digit $5$ in the number $7658321$ is successor of $49999$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

(a) Place value of $3$ in number $27543765$ is $3000$
(b) Place value of $6$ in number $6734591$ is $6000000$ which is predecessor of $6000001$
(c) In the number $1876523$, place value of $1$ is $1000000$
(d) Place value of $5$ in $7658321$ is $50000$ which is successor of $49999$.

Hence the option B is incorrect.

Multiple choice economics partition values introduction to statistics introduction to statistical method and econometrics frequency distribution tables and graphs

Find the correct descending order
$2, 0, 3, 4, 1, 2, 3, 5$

  1. $5, 4, 3, 2,3, 2, 1, 0$
  2. $5, 4, 3, 3, 2, 2, 1, 0$
  3. $4,5, 3, 3, 2, 2, 1, 0$
  4. $5, 4, 3, 3, 2, 2, 0,1$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Given, series is $2,0,3,4,1,2,3,5$
Descending means high to low.
Therefore, the descending order is $5,4,3,3,2,2,1,0$.
Multiple choice maths equivalent fractions comparing and ordering fractions comparing fractions fractions and its related operations

What is the least number if $\displaystyle {\frac{3}{5},\, \frac{9}{5},\, \frac{1}{5},\, \frac{7}{5}}$ are arranged in ascending or descending order?

  1. $\dfrac39$
  2. $\dfrac15$
  3. $\dfrac75$
  4. $\dfrac35$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The given numbers can be arranged in the ascending order as:
$ {\cfrac{1}{5}\, >\, \cfrac{3}{5}\, >\, \cfrac{7}{5}\, >\, \cfrac{9}{5}}$
Greatest number $= \cfrac{9}{5}$ and Least number $= \cfrac{1}{5}$