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Finding the Fourth Proportional to 418.60, 628.21 and 288.90

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Solution

The fourth proportional to 418.60, 628.21 and 288.90 is: 433.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.60 : 628.21 = 288.90 : x
  2. Step 2: Convert to fraction form
    418.60/628.21 = 288.90/x
  3. Step 3: Cross multiply
    418.60x = 628.21 × 288.90
  4. Step 4: Simplify right side
    418.60x = 181,488.61
  5. Step 5: Solve for x
    x = 181,488.61/418.60
  6. Step 6: Final answer
    x = 433.56

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.