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Finding the Fourth Proportional to 398.76, 546.81 and 397.80

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Solution

The fourth proportional to 398.76, 546.81 and 397.80 is: 545.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.76 : 546.81 = 397.80 : x
  2. Step 2: Convert to fraction form
    398.76/546.81 = 397.80/x
  3. Step 3: Cross multiply
    398.76x = 546.81 × 397.80
  4. Step 4: Simplify right side
    398.76x = 217,521.02
  5. Step 5: Solve for x
    x = 217,521.02/398.76
  6. Step 6: Final answer
    x = 545.49

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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.