Time for another great math challenge for those who enjoy solving mathematics and critical thinking challenges.
Challenge:
The perimeter of a square is 13 cm and the perimeter of an equilateral triangle is 7 cm. What is the difference of a side of the square and a side of a triangle?
A- \(\frac{7}{13}\) cm
B- \(\frac{11}{12}\) cm
C- \(1\frac{1}{4}\) cm
D- \(2\frac{1}{4}\) cm
E- \(\frac{13}{7}\) cm
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The correct answer is B.
The perimeter of a square is 13cm. Therefore, one side of the square is \(\frac{13}{4}\) cm.
The perimeter of the equilateral triangle is 7cm. Therefore, one side of the triangle is \(\frac{7}{3}\) cm.
The difference of a side of the square and a side of a triangle is:
\(\frac{13}{4} – \frac{7}{3} = \frac{39-28}{12} = \frac{11}{12}\) cm