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Finding the Fourth Proportional to 540.80, 811.16 and 280.68

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Solution

The fourth proportional to 540.80, 811.16 and 280.68 is: 420.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    540.80 : 811.16 = 280.68 : x
  2. Step 2: Convert to fraction form
    540.80/811.16 = 280.68/x
  3. Step 3: Cross multiply
    540.80x = 811.16 × 280.68
  4. Step 4: Simplify right side
    540.80x = 227,672.33
  5. Step 5: Solve for x
    x = 227,672.33/540.80
  6. Step 6: Final answer
    x = 420.99

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.