A rectangle has a perimeter of 40 cm. If the length is 15 cm, what is the width?
Category: Math · Difficulty: hard
Hint: Use the perimeter formula: P = 2(l + w).
Answer
5 cm
Explanation
Using P = 2(15 + w) = 40 gives w = 5 cm.
This is a hard math riddle — a tricky one that takes a little thought. The answer is 5 cm.
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