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Finding the Fourth Proportional to 398.30, 545.76 and 393.17

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Solution

The fourth proportional to 398.30, 545.76 and 393.17 is: 538.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.30 : 545.76 = 393.17 : x
  2. Step 2: Convert to fraction form
    398.30/545.76 = 393.17/x
  3. Step 3: Cross multiply
    398.30x = 545.76 × 393.17
  4. Step 4: Simplify right side
    398.30x = 214,573.73
  5. Step 5: Solve for x
    x = 214,573.73/398.30
  6. Step 6: Final answer
    x = 538.73

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.