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Finding the Fourth Proportional to 518.79, 715.95 and 285.91

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Solution

The fourth proportional to 518.79, 715.95 and 285.91 is: 394.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.79 : 715.95 = 285.91 : x
  2. Step 2: Convert to fraction form
    518.79/715.95 = 285.91/x
  3. Step 3: Cross multiply
    518.79x = 715.95 × 285.91
  4. Step 4: Simplify right side
    518.79x = 204,697.26
  5. Step 5: Solve for x
    x = 204,697.26/518.79
  6. Step 6: Final answer
    x = 394.57

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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.