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Finding the Fourth Proportional to 398.60, 550.10 and 300.20

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Solution

The fourth proportional to 398.60, 550.10 and 300.20 is: 414.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.60 : 550.10 = 300.20 : x
  2. Step 2: Convert to fraction form
    398.60/550.10 = 300.20/x
  3. Step 3: Cross multiply
    398.60x = 550.10 × 300.20
  4. Step 4: Simplify right side
    398.60x = 165,140.02
  5. Step 5: Solve for x
    x = 165,140.02/398.60
  6. Step 6: Final answer
    x = 414.30

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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.