Subject
Quantitative Aptitude
Topic
Areas & Volumes
The length of a rectangle is twice its breadth. If its length is decreased by 5 cm and breadth is increased by 5 cm, the area of the rectangle is increased by 75 sq.cm. Find the length of the rectangle?
The length of a rectangle is twice its breadth. If its length is decreased by 5 cm and breadth is increased by 5 cm, the area of the rectangle is increased by 75 sq.cm. Find the length of the rectangle?
ক)
10cmখ)
30cmগ)
40cmঘ)
20cmExplanation
Let the breadth of the given rectangle be x then length is 2x. thus area of the given rect is after dec 5cm from length and inc 5cm breadth , new lenght becomes 2x-5 and breadth is x+5.thus new area =(2x-5)(x+5) = since new area is 75 units greater than original area thus 5x=75+25 5x=100 therefore x=20 hence length of the rectangle is 40 cm.Related questions
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