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Finding the Fourth Proportional to 475.20, 708.89 and 421.20

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Solution

The fourth proportional to 475.20, 708.89 and 421.20 is: 628.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    475.20 : 708.89 = 421.20 : x
  2. Step 2: Convert to fraction form
    475.20/708.89 = 421.20/x
  3. Step 3: Cross multiply
    475.20x = 708.89 × 421.20
  4. Step 4: Simplify right side
    475.20x = 298,582.36
  5. Step 5: Solve for x
    x = 298,582.36/475.20
  6. Step 6: Final answer
    x = 628.33

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.