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Question
The length of a rectangular field is twice its breadth. Jamal jogged around it four times and covered a distance of 6 km. What is the length of the field?
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Solution
Let breadth of rectangular field = x m
Then, length of rectangular field = 2x m
∵ Distance covered in one round = Perimeter
∴ Distance covered in four rounds = 4 × Perimeter
⇒ 4 × 2(l + b) = 6 km ...[∵ Perimeter = 2(length + breadth)]
⇒ 8 × (l + b) = 6000 m ...[∵ 1 km = 1000 m]
⇒ 8(2x + x) = 6000 m
⇒ 24x = 6000 m
⇒ `(24x)/24 = 6000/24` ...[Dividing both sides by 24]
⇒ x = 250 m
∴ Length of the field = 2x = 2 × 250 = 500 m
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