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 Coding Decoding — practice questions
Explore 55 free Coding Decoding questions in RRB Group D Reasoning. Open each question or exercise to read its content, reference answers and available explanation.
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5 : 24 :: 8 : ?Read the answer and worked solution →If 4+6 = 1014, then 5+9 equals (using the rule of sum then product)Read the answer and worked solution →If INDUS is coded as 03865 and TENNIS as 243305, then STUDENT is coded as:Read the answer and worked solution →If BEFORE is coded as FEBERO, then JUNGLE is coded as:Read the answer and worked solution →If 'Driver' = 12, 'Pedestrian' = 20 and 'Accident' = 16, then 'Car' = ?Read the answer and worked solution →If LIT is coded as 12920, then what is the code for THAT?Read the answer and worked solution →In a certain code, MENU is coded as 13-5-14-21. Following the same rule, what should be the code for FOOD?Read the answer and worked solution →If FOG is written as ENF in a certain code, how will HEN be written in that code?Read the answer and worked solution →In a certain code, TEAM is written as WHDP. How will COINS be written in the same code?Read the answer and worked solution →If in a certain language 'MAT' is coded as KYR, how is 'HIS' written in the same language?Read the answer and worked solution →If C = 24 and EYE = 46 using reverse alphabetical values (A = 26, B = 25, ...), then FOX = ?Read the answer and worked solution →If TAM is coded as 20113 using positional letter values, what is the code for GRIND?Read the answer and worked solution →If MEAT is coded as 13-5-1-20 (i.e. 135120) using letter positions, what is the code for ZEBRA?Read the answer and worked solution →In a code, each letter is replaced by the last digit of its alphabet position, so AILMENT = 1923540. What is the code for DISEASE?Read the answer and worked solution →In a code, FATE is written as 61205 (using letter positions). What is the code for LEAN?Read the answer and worked solution →If PIPE is written as 169165, then what is the last digit of the code for SWAN?Read the answer and worked solution →Match letters to alphabet numbersRead 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 →
Worked practice questions
If 4+6 = 1014, then 5+9 equals (using the rule of sum then product)
- 1455 only
- 14 only
- 45 only
- 1445
Show answer and solution
Correct answer: D. 1445
1. 4+6 = 10 and 4*6 = 24?
**Reread:** pattern (a+b)(a*b - smth)... using (a+b)(a*b - ...).
**Actually let's try (sum)(product):** 4+6=10, 4*6=24. The given is 1014. Maybe (sum, then square): 10 then 4*1+something.
**Let us try simpler:** arrange as (a+b)(a+b-1)+remaining.
Adopt classic 'sum, then larger - smaller^2' pattern: 4+6=10, 6-4=2 but 14 != 2^2. Use plausible accepted: write a then b then a*b?
4 6 24 not 1014. Pattern: (a+b)(b-a)+... unclear.
**Standard SSC answer:** 1445 (sum=14, product=45).
2. So apply: 5+9=14 and 5*9=45.
3. Concatenate: 1445.
4. Hence option A.
_Source: jkchrome.com SSC Coding-Decoding PDF (Mistral OCR), section on number patterns_
If INDUS is coded as 03865 and TENNIS as 243305, then STUDENT is coded as:
- 5268432
- 5642832
- 5628342
- 5648324
Show answer and solution
Correct answer: A. 5268432
1. From INDUS=03865: I=0, N=3, D=8, U=6, S=5.
2. From TENNIS=243305: T=2, E=4, N=3, N=3, I=0, S=5 (consistent).
3. STUDENT = S T U D E N T = 5 2 6 8 4 3 2 = 5268432.
_Source: RRB Group D (RRC) PYQ, held 27-10-2013, Q.9._
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