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Finding the Fourth Proportional to 418.60, 628.34 and 402.21

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Solution

The fourth proportional to 418.60, 628.34 and 402.21 is: 603.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.60 : 628.34 = 402.21 : x
  2. Step 2: Convert to fraction form
    418.60/628.34 = 402.21/x
  3. Step 3: Cross multiply
    418.60x = 628.34 × 402.21
  4. Step 4: Simplify right side
    418.60x = 252,724.63
  5. Step 5: Solve for x
    x = 252,724.63/418.60
  6. Step 6: Final answer
    x = 603.74

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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.