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Finding the Fourth Proportional to 418.60, 628.80 and 403.30

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Solution

The fourth proportional to 418.60, 628.80 and 403.30 is: 605.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.60 : 628.80 = 403.30 : x
  2. Step 2: Convert to fraction form
    418.60/628.80 = 403.30/x
  3. Step 3: Cross multiply
    418.60x = 628.80 × 403.30
  4. Step 4: Simplify right side
    418.60x = 253,595.04
  5. Step 5: Solve for x
    x = 253,595.04/418.60
  6. Step 6: Final answer
    x = 605.82

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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.