A rectangle has a perimeter of 36 cm and its length is twice its width. What is its area?
Answer and explanation
Correct answer: B. 72 square centimetres
- Step 1: With width w and length 2w, the perimeter is 2(w + 2w) = 6w = 36, so w = 6 and the length is 12.
- Step 2: Area = 6 x 12 = 72.
Answer
72 square centimetres.
Why not the others: The other areas come from sides that do not satisfy both the perimeter and the 2 : 1 condition.
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