CSAT (Aptitude)·Prelims Questions
Number Coding — Prelims Questions
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Version 1Updated 5 Mar 2026
Q1easy
In a certain code, 15 is written as 225, 23 is written as 529, and 34 is written as 1156. How is 42 written in that code?
Q2medium
If in a certain code, 246 is written as 8, 369 is written as 18, and 482 is written as 14, then how is 573 written?
Q3hard
In a code language, if MONDAY is coded as 123456 and TEAM is coded as 8954, then how is MATE coded?
Q4medium
If 5 × 3 = 28, 7 × 4 = 45, 9 × 2 = 29, then 6 × 8 = ?
Q5easy
In a certain coding system, 1234 becomes 4321, 5678 becomes 8765, and 9012 becomes 2109. What does 3456 become?