alleryStart learning →5 : 24 :: 8 : ?
- 81
- 63
- 48
- 56
Show answer and solution
Correct answer: B. 63
Pattern: n² - 1. 5² - 1 = 24. 8² - 1 = 63.
RRB Group D Reasoning & Aptitude — practice questions
Explore 21 free Reasoning & Aptitude questions in RRB Group D Reasoning. Open each question or exercise to read its content, reference answers and available explanation.
Practise Reasoning & Aptitude with Quill →Reasoning & Aptitude questions and exercises with answers
Showing questions 1–21 of 21.
5 : 24 :: 8 : ?Read the answer and worked solution →Match each proposition form to its letterRead the answer and worked solution →Universal or particular? Affirmative or negative?Read the answer and worked solution →Affirmative or negative?Read the answer and worked solution →Naming the formRead the answer and worked solution →True or false: what conversion allowsRead the answer and worked solution →Tap every inference that is actually validRead the answer and worked solution →Complete the four formsRead the answer and worked solution →True or false: what a universal claim coversRead the answer and worked solution →Deduction or induction?Read the answer and worked solution →Order the steps: test a syllogismRead the answer and worked solution →True or false: reasoning from two premisesRead the answer and worked solution →Assertion and reasonRead the answer and worked solution →Two are true, one is notRead the answer and worked solution →Three of these are wrong. Find the one that holds.Read the answer and worked solution →Flip and pair: letter with statementRead the answer and worked solution →Spot the one that does not belongRead the answer and worked solution →Deduction against inductionRead the answer and worked solution →Tap every statement that follows from 'All cats are animals'Read the answer and worked solution →Complete the conversion ruleRead the answer and worked solution →Which reversal is safe?Read the answer and worked solution →
Worked practice questions
Match each proposition form to its letter
Read exercise and reference answers
- Matching pairs
- Left
- A
- Right
- Universal Affirmative: All S is P
- Left
- E
- Right
- Universal Negative: No S is P
- Left
- I
- Right
- Particular Affirmative: Some S is P
- Left
- O
- Right
- Particular Negative: Some S is not P
The four classical forms.
Syllogism questions in competitive papers are built entirely from these.
Source: Logic: Deductive and Inductive, Carveth Read (1898), public domain.
Universal or particular? Affirmative or negative?
Read exercise and reference answers
- Items
- Item
- All S is P
- Category
- Universal
- Item
- No S is P
- Category
- Universal
- Item
- Covers the whole subject
- Category
- Universal
- Item
- Some S is P
- Category
- Particular
- Item
- Some S is not P
- Category
- Particular
- Item
- Covers only part of the subject
- Category
- Particular
- Categories
- Item
- Universal
- Item
- Particular
Two independent axes: how much of the subject is covered, and whether the statement affirms or denies. Source: Logic: Deductive and Inductive, Carveth Read (1898), public domain.
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