A rectangle's length increases by 10% and breadth decreases by 10%. What is the area of the new rectangle:_________?
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Answer: C. decreased by 1 %
Explanation
Successive percentage changes in dimensions alter the total rectangle area by combining multipliers sequentially. Increasing length by ten percent multiplies it by one point one while decreasing breadth multiplies it by zero point nine. Multiplying one point one by zero point nine yields zero point nine nine representing a one percent net decrease. The net percentage change resulting from equal successive percentage increases and decreases always yields a net decrease. Area of a rectangle is calculated as the direct product of its length multiplied by its breadth. Percentages represent fractional values out of one hundred, facilitating straightforward algebraic scaling calculations.
Option A claims area neither increases nor decreases which ignores the compound mathematical effect of successive percentages. Option B claims a one percent increase which incorrectly treats opposite percentage changes as completely cancelling out. Option D claims a ten percent decrease which confuses individual dimensional changes with total calculated area change.
- Subject
- Mathematics
- Category
- Mathematics
- Topic
- —
- Difficulty
- medium
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