Geometry Puzzle – Challenge 69
Who can solve this math puzzle quickly? This is a great logic challenge for those who love critical thinking challenges. Let's challenge your brain!
Challenge:
A length of a rectangle is increased by \(20\%\). What percent of its width should be decreased to keep the area of the rectangle the same?
A- \(15\%\)
B- \(16\frac{2}{3}\%\)
C- \(20\%\)
D- \(25\%\)
E- \(30\%\)
The Absolute Best Book to Challenge Your Smart Student!
The correct answer is B.
The area of a rectangle is the product of its width and length. Let x be the area of the rectangle.
Area of a rectangle = Width × Length = x
Length → 1.2Length → Area of a rectangle = Width × 1.2Length = x
Let W1 be the width of the first rectangle and W2 be the width of the second rectangle.
W1 × 1.2L = W2 × L → W1 × 1.2 = W2 → W1 \(= \frac{1}{1.2}\)W2 →
W1 \(= \frac{5}{6 }\)W2
To keep the area of the rectangle the same \(\frac{1}{6 }\) or \(16\frac{2}{3}\) percent of the width should be decreased.
The Best Books to Ace Algebra
Related to This Article
More math articles
- Organizing the Products: How to Sorting Results from Multiplying Fractions and Whole Numbers
- How to Solve Word Problems of Writing Variable Expressions
- What Does SHSAT Stand for?
- FREE 6th Grade Common Core Math Practice Test
- Journey to the Stars: How to Solve Circles Word Problems
- How to Graph Transformation on the Coordinate Plane: Reflection?
- A Comprehensive Collection of Free TABE Math Practice Tests
- FREE SAT Math Practice Test
- 4th Grade New York State Assessments Math Worksheets: FREE & Printable
- Algebra Puzzle – Challenge 52
What people say about "Geometry Puzzle – Challenge 69 - Effortless Math: We Help Students Learn to LOVE Mathematics"?
No one replied yet.