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#0106
Successive Percentage Change
EasyAptitude15 min10 XP
Problem
A value increases by 20% and then decreases by 10%. What is the final percentage change from the original?
Why This Matters
Many aptitude mistakes come from adding percentages directly instead of applying them successively.
Examples
Example 1
Input+20%, then -10%
Output+8%
The 10% decrease is taken on 120, not on 100.
Constraints
- Return the exact structure requested.
- Handle the edge cases mentioned in the prompt.
- Prefer clear logic over clever one-liners.
CodeReasoning
A value increases by 20% and then decreases by 10%. What is the final percentage change from the original?
Visible browser tests run here when available.
Testcases1 visible / 3 hidden categories
Core example
Input+20%, then -10%
Expected+8%
The 10% decrease is taken on 120, not on 100.
Hidden Test Categories
two increasestwo decreasesreverse order