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Finding the Fourth Proportional to 400.90, 545.80 and 397.30

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Solution

The fourth proportional to 400.90, 545.80 and 397.30 is: 540.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    400.90 : 545.80 = 397.30 : x
  2. Step 2: Convert to fraction form
    400.90/545.80 = 397.30/x
  3. Step 3: Cross multiply
    400.90x = 545.80 × 397.30
  4. Step 4: Simplify right side
    400.90x = 216,846.34
  5. Step 5: Solve for x
    x = 216,846.34/400.90
  6. Step 6: Final answer
    x = 540.90

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Why These Related Problems?

These problems maintain the same ratio (1.36) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.