Sherry a naughty boy after lot of convincing by his mother has agreed to mow the farmlawn,which is a 30 m by 40 m rectangle.The mower mows a 1 m wide strip.If sherry starts at one corner and mows around the lawn towards the centre, about how many times would he go around before he has mowed half the lawn?

Dear student
Area of the rectangle = 30×40 = 1200 = full area So, half area = 12002 = 600  In the 1st round, he covers 40+40+28+28 = 136 In the 2nd round, he covers 38+38+26+26 = 128 In the 3rd round, he covers 36+36+24+24 = 120 In the 4th round, he covers 34+34+22+22 = 112 In the 5th round, he covers 32+32+20+20 = 104 Total =136+128+120+112+104= 600 So, 5 rounds. 
Regards

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