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Finding the Fourth Proportional to 518.28, 715.16 and 285.40

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Solution

The fourth proportional to 518.28, 715.16 and 285.40 is: 393.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.28 : 715.16 = 285.40 : x
  2. Step 2: Convert to fraction form
    518.28/715.16 = 285.40/x
  3. Step 3: Cross multiply
    518.28x = 715.16 × 285.40
  4. Step 4: Simplify right side
    518.28x = 204,106.66
  5. Step 5: Solve for x
    x = 204,106.66/518.28
  6. Step 6: Final answer
    x = 393.82

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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.