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Finding the Fourth Proportional to 518.81, 715.71 and 308.87

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Solution

The fourth proportional to 518.81, 715.71 and 308.87 is: 426.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.81 : 715.71 = 308.87 : x
  2. Step 2: Convert to fraction form
    518.81/715.71 = 308.87/x
  3. Step 3: Cross multiply
    518.81x = 715.71 × 308.87
  4. Step 4: Simplify right side
    518.81x = 221,057.77
  5. Step 5: Solve for x
    x = 221,057.77/518.81
  6. Step 6: Final answer
    x = 426.09

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.