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Finding the Fourth Proportional to 518.66, 715.78 and 285.79

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Solution

The fourth proportional to 518.66, 715.78 and 285.79 is: 394.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.66 : 715.78 = 285.79 : x
  2. Step 2: Convert to fraction form
    518.66/715.78 = 285.79/x
  3. Step 3: Cross multiply
    518.66x = 715.78 × 285.79
  4. Step 4: Simplify right side
    518.66x = 204,558.47
  5. Step 5: Solve for x
    x = 204,558.47/518.66
  6. Step 6: Final answer
    x = 394.40

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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.