A rectangle has a perimeter of 30 and its length is twice its width. What is its area?
Answer and explanation
Correct answer: B. 50
- 75 assumes dimensions and , which gives a perimeter of rather than .
- 100 squares the length () rather than computing length times width ().
- 150 multiplies the entire perimeter directly by the width (), misapplying the area formula.
- 100 squares the length () rather than computing length times width ().
- 150 multiplies the entire perimeter directly by the width (), misapplying the area formula.
- Step 1: Set up the perimeter formula with width and length : .
- Step 2: Solve for width and length: , so .
- Step 3: Calculate the area: .
Answer
50.
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