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there is a footpath around a rectangular garden with kength 30m and breadth 20m. The area of the large rectangular plot including the footpath and garden is 816m². Find the width of the footpath? |
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Answer» Step-by-step explanation: A rectangular garden 40 m ×30 m is surrounded from outside by a PATH of equal width. if the area of the path is 456 m² , find the width of the path? ANSWER : FOR RECTANGLE LENGTH = 40M BREADTH = 30M SO AREA OF GARDEN=L×B =40×30 =1200M² SO LET THE SUM OF WIDTH BE X FOR THE PATH FROM BOTH SIDES SO 2(WIDTH)=X SO OVERALL LENGTH = (40+X)M AND OVERALL BREADTH = (30+X)M SO OVERALL AREA = L×B =(40+X)(30+X) =1200+40X+30X+X² = (X²+70X+1200)M NOW IT IS GIVEN THAT AREA OF PATH=456M² SO AREA OF PATH = OVERALL AREA-AREA OF GARDEN 456=X²+70X+1200-1200 X²+70X-456=0 So by splitting the middle term method X²+76X-6X-456=0 X(X+76)-6(X+76)=0 (X+76)(X-6)=0 SO X+76=0 OR X-6=0 X=-76 OR X=6 BUT BREADTH CAN NEVER BE NEGATIVE SO X=-76 IS REJECTED SO X=6 IS ACCEPTED SO 2(WIDTH)=X WIDTH=X/2 WIDTH=6/2 WIDTH=3M HENCE THE WIDTH OF THE PATH IS 3 METRES |
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