If in a code, 52 – 36 = 97 and 46 – 78 = 1213, then how 58 – 62 can be encoded?
2024
If in a code, 52 – 36 = 97 and 46 – 78 = 1213, then how 58 – 62 can be encoded?
- A.
1520
- B.
88
- C.
2015
- D.
129
Show answer & explanation
Correct answer: D
Concept: In this coding-decoding pattern, each number pair is decoded digit by digit — the tens digits of the two numbers are added together and adjusted one way, while the units digits are added together and adjusted the opposite way; writing the two adjusted sums one after another gives the code.
Application:
52 – 36: tens digits 5 and 3 sum to 8; adding 1 gives 9. Units digits 2 and 6 sum to 8; subtracting 1 gives 7. Writing 9 then 7 gives 97, matching the given code.
46 – 78: tens digits 4 and 7 sum to 11; adding 1 gives 12. Units digits 6 and 8 sum to 14; subtracting 1 gives 13. Writing 12 then 13 gives 1213, matching the given code.
58 – 62: tens digits 5 and 6 sum to 11; adding 1 gives 12. Units digits 8 and 2 sum to 10; subtracting 1 gives 9. Writing 12 then 9 gives 129.
Cross-check: The same rule (first-digit-sum + 1, second-digit-sum − 1) reproduces both given codes 97 and 1213 exactly, so the pattern is confirmed before it is applied to the new pair; no other digit-combination rule fits both given examples simultaneously.
Hence, 58 – 62 is encoded as 129.