Abuilding measuring 90m by60m is to be built. a paved area of uniform will surround the building. the area is to have an are of 9000 metres squared. how wide is the paved area

A= 9000m squared and A= base(width)*hight or A=b*h so divide 9000m by 60m
9000/60=(1050) 60 120 180 240 300 360 420 480 and so on
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