Subject
Quantitative Aptitude
Topic
Percentage
If a length of a rectangle is increased by 30% and the width is decreased by 30%, then the area will be-
If a length of a rectangle is increased by 30% and the width is decreased by 30%, then the area will be-
ক)
Decreased by 9%খ)
Increased by 9%গ)
Decreased by 18%ঘ)
Increased by 16%Explanation
Let, x = original width and y = original length Then, Area = xy After change: width = x - 0.30x = 0.70x length = y + 0.30y = 1.30y Then, Area = (0.70x)*(1.30y) = 0.91xy Change in area: (xy - 0.91xy) =0.09xy Percent change in area: (0.09xy)/xy *100 =0.09 * 100 =9% decrease in areaRelated questions
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