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Finding the Fourth Proportional to 410.68, 615.72 and 280.72

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Solution

The fourth proportional to 410.68, 615.72 and 280.72 is: 420.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    410.68 : 615.72 = 280.72 : x
  2. Step 2: Convert to fraction form
    410.68/615.72 = 280.72/x
  3. Step 3: Cross multiply
    410.68x = 615.72 × 280.72
  4. Step 4: Simplify right side
    410.68x = 172,844.92
  5. Step 5: Solve for x
    x = 172,844.92/410.68
  6. Step 6: Final answer
    x = 420.87

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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.