Home / 135-285

Finding the Third Proportional to 135 and 285

Calculator

Solution

The third proportional to 135 and 285 is: 601.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    135 : 285 = 285 : x
  2. Step 2: Convert to fraction form
    135/285 = 285/x
  3. Step 3: Cross multiply
    135x = 285 × 285
  4. Step 4: Simplify right side
    135x = 81,225
  5. Step 5: Solve for x
    x = 81,225/135
  6. Step 6: Final answer
    x = 601.67

Related Problems

Find third proportional to 67.50 and 142.50
Half scale
Find third proportional to 270 and 570
Double scale
Find third proportional to 137 and 289
Similar ratio
Find third proportional to 202.50 and 427.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (2.11) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.