Input – Output questions test the student’s ability to understand the pattern given in the input and subsequent steps, and extrapolate that to answer the questions.
These Input-Output Reasoning Questions are usefull for Bank Exams.
These Input-Output Reasoning Questions are usefull for Bank Exams.
Generally there are three types of Input – Output questions:
(a) Based upon reasoning - In these questions, the words or the numbers are arranged as per some fixed order or reasoning. For example, elements may be arranged in steps as per alphabetical order in case of letters or it may be an ascending or descending order in case of numbers or steps may be given in the order of sum of digits of the number.
(b) Based upon simple replacement algorithm - In these questions, elements given in the input are shifted according to a fixed pattern.
(c) Based upon arithmetic operation – Typically, in these questions, input will be some number given and subsequent steps are obtained by performing different arithmetic operations on the numbers given in the input.
Structure of the Question:
Every question will start with an Input – either numeric or words or a combination – followed by Steps. Understand this with the help of following example:
Ques 1. An electronic device when fed with numbers rearranges them in a particular order following certain rules. Following is the data fed (input) and Steps obtained:
Input: 18, 12, 27,11,14,25
Step I : 27, 18, 12,11,14,25
Step II : 27, 25, 18,12,11,14
Step III : 27, 25, 18,14,12,11
Step III is the last step for the given data (input).
How to approach problems:
On the basis of the steps given, we are required to decide if it is based upon reasoning or based upon simple replacement algorithm.
For understanding the logic of arrangement you are advised to follow some steps:
Step I : Look at the last step and try to find out if there is a pattern or reasoning in the occurrence of the elements. If yes, it is reasoning based problem and if no, it is simple replacement algorithm.
This reasoning can be:
i. Ascending / descending order of the numbers
ii. Sum of the digits of the numbers
iii. Prime numbers first, then composite numbers in ascending / descending order
iv. Alphabetical order of the words
v. Number of letters in the words
vi. Combination of the rules iv and v.
Understand that these rules are not exhaustive, and you may get a question set that is using a rule beyond all that is mentioned here.
Step II : If there is no reasoning in the elements as given in the steps, then try to find out a possible replacement algorithm. Have a quick glance at every step to know how this is being carried out
Coming back to the Ques1 given earlier:
Taking a quick glance at the last step shows that numbers are in descending order. Analyzing the previous steps also confirm that the numbers are rearranged in descending order.
Thumb rules:
1. If question mentions that step N (N may be 3,4,5,6,7 or more) is the last step, it is almost certain that there is a reasoning behind the steps generated using the elements given in the input.
2. In questions where some reasoning is used to generate the next steps, it is not possible to go to previous step or to the input using any step given ahead.
For example, it will not be possible to go to step IV or to input using step V or step VI etc.
For example, it will not be possible to go to step IV or to input using step V or step VI etc.
Questions 2 - 5: Read the instruction given below and solve the questions based on it.
An electronic device when fed with the numbers, rearranges them in a particular order following certain rules. The following is a step-by-step process of rearrangement for the given input of numbers
Input : 85, 16,36,04,19,97,63,09
Step I : 97, 85,16,36,04,19,63,09
Step II : 97,85,63,16,36,04,19,09
Step III : 97,85,63,36,16,04,19,09
Step IV : 97,85,63,36,19,16,04,09
Step V : 97,85,63,36,19,16,09,04
(For the given input, step V is the last step). Now study the logic and rules followed in the above steps and find out appropriate step for the question given below for the given input.
Explanation:
There are two things that can be observed:
(a) Step V is the last step – it indicates that there is some reasoning used to formulate the steps,
(b) Last step has the elements that are arranged perfectly in descending order.
(a) Step V is the last step – it indicates that there is some reasoning used to formulate the steps,
(b) Last step has the elements that are arranged perfectly in descending order.
Ques 2. Which of the following will be step v for the given input?
Input: 25,08,35,11,88,67,23
(a) 88,67,35,11,88,67,23
(b) 88,67,35,25,08,11,23
(c) 88,11,23,25,35,67,23
(d) 88, 67, 35, 25, 23, 08, 11
Solution:- We are going to arrange the numbers in descending order taking numbers one by one.
Step 1 = 88, 25,08,35,11, 67, 23
Step 2 = 88, 67, 25, 08, 35, 11, 23
Step 3 = 88, 67, 35, 25, 08, 11, 23
Step 4 = 88, 67, 35, 25, 23, 08, 11
Hence option (d) is the answer.
Ques 3. Which of the following will be step III for given input?
Input : 09, 25, 16, 30, 32, 18, 17, 06
(a) 32, 09, 25, 16, 30, 18, 17, 06
(b) 32, 30, 09, 25, 16, 18, 17, 06
(c) 32, 30, 25, 09, 16, 18, 17, 06
(d) 32, 25, 09, 16, 30, 18, 17, 06
Solution:- We are going to arrange the numbers in descending order taking numbers one by one.
Step 1 = 32, 09, 25, 16, 30, 18, 17, 06
Step 2 = 32, 30, 09, 25, 16, 18, 17, 06
Step 3 = 32, 30, 25, 09, 16, 18, 17, 06
Hence option (C) is the answer.
Ques 4. Which of the following will be the last step for the given input?
Input : 16,09,25,27,06,05
(a) Step 1
(b) Step 2
(c) Step 3
(d) Step 4
Solution:- We are going to arrange the numbers in descending order taking numbers one by one.
Step 1 = 27, 16, 09, 25, 06, 05
Step 2 = 27, 25, 16, 09, 06, 05
Step 2 gives all the elements arranged in the descending order. Hence this is the last step. Hence option (b) is the answer.
Ques 5. If step IV is as given, then which of the following was the input?
Step IV: 92, 86,71,69,15, 19,06, 63,58
(a) 86, 92, 69, 71, 15, 19, 06, 63, 58
(b) 15, 86, 19, 92, 06, 69, 63, 58, 71
(c) 15, 19, 06, 63, 58, 86, 92, 69, 71
(d) Cannot be determined
Solution – We cannot go back to previous step or to the input as we do not know which element came from which place. Hence option (d) cannot be determined is the answer.
Questions 6 to 10: Read the instruction given below and solve the questions based on it.
A word arrangement machine, when given an input line of words, rearrange them following a particular rule. Following presents the input and steps generated as per this rule:
Input: Go for to though by easy to access at
Step I : Access go for to though by easy to at
Step II: Access at go for to though by easy to
Step III: Access at by go for to though easy to
Step IV: Access at by go for to though easy to
Step V: Access at by easy for go to though to
Step VI: Access at by easy for go to though to
Step VI: Access at by easy for go though to to
Step VII: Access at by easy for go though to to
(Step VII is the last step for this input.) As per the rules followed in the above steps, find out in the given questions the appropriate step for the given input.
Explanation:
A quick glance at the last step gives us an idea that words have been arranged alphabetically 1st and if the 1st letter is same, then 2nd letter decides the order of occurrence. This sequencing is also knows as sequencing based upon dictionary usage.
Ques 6. Input: Story for around on was he at”. Which of the following will be Step IV for the given input?
(a) Around at for he on was story
(b) Around at for he on story was
(c) Around at for he story on was
(d) Around at he for story on was
Solution:
Step 1 = Around Story for on was he at
Step 2 = Around at Story for on was he
Step 3 = Around at for Story on was he
Step 4 = Around at for he Story on was
Hence option (c) is the answer.
Ques 7. Input: “Every ant peer to an for”. Which of the following steps would the last step for this input?
(a) II
(b) III
(c) IV
(d)V
(b) III
(c) IV
(d)V
Solution:
Step 1 = an every ant peer to for
Step 2 = an ant every peer to for
Step 3 = an ant every for peer to
This is the last step for this input as all the words are alphabetically arranged now. Hence option (b) is the answer.
Ques 8. Step II of an input is as follows: “Do and pet to on that”. Which of the following would definitely be the input?
(a) Do on pet to and that
(b) Do pet to and that on
(c) Do and pet to on that
(d) Cannot be determined
Solution – We cannot go back to input from any step in any question set that is based upon some reasoning. Hence answer is option (d) cannot be determined.