A number is first decreased by 20% and then increased… - Arithmetical Reasoning (Reasoning) Solved Question

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Q · Arithmetical Reasoningmedium · 45s

A number is first decreased by 20% and then increased by 25%. The final result is 90. Find the original number.

TopicArithmetical Reasoning

Question Typemultiple choice

Difficultymedium

Marking+1 / −0.25

Test Duration30 min

Step-by-Step Solution

Every step explained - no skipped algebra.

Let the original number = x

After 20% decrease → 80% of x = 0.8x

After 25% increase → 0.8x × 1.25 = 90

So, 1.0x = 90

x = 90

Final Answer: Option B - 90