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Finding the Fourth Proportional to 418.70, 628.05 and 415.10

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Solution

The fourth proportional to 418.70, 628.05 and 415.10 is: 622.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.70 : 628.05 = 415.10 : x
  2. Step 2: Convert to fraction form
    418.70/628.05 = 415.10/x
  3. Step 3: Cross multiply
    418.70x = 628.05 × 415.10
  4. Step 4: Simplify right side
    418.70x = 260,703.56
  5. Step 5: Solve for x
    x = 260,703.56/418.70
  6. Step 6: Final answer
    x = 622.65

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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.