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Finding the Fourth Proportional to 518.68, 715.80 and 285.80

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Solution

The fourth proportional to 518.68, 715.80 and 285.80 is: 394.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.68 : 715.80 = 285.80 : x
  2. Step 2: Convert to fraction form
    518.68/715.80 = 285.80/x
  3. Step 3: Cross multiply
    518.68x = 715.80 × 285.80
  4. Step 4: Simplify right side
    518.68x = 204,575.64
  5. Step 5: Solve for x
    x = 204,575.64/518.68
  6. Step 6: Final answer
    x = 394.42

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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.