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Finding the Fourth Proportional to 418.70, 628.05 and 272.90

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Solution

The fourth proportional to 418.70, 628.05 and 272.90 is: 409.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.70 : 628.05 = 272.90 : x
  2. Step 2: Convert to fraction form
    418.70/628.05 = 272.90/x
  3. Step 3: Cross multiply
    418.70x = 628.05 × 272.90
  4. Step 4: Simplify right side
    418.70x = 171,394.85
  5. Step 5: Solve for x
    x = 171,394.85/418.70
  6. Step 6: Final answer
    x = 409.35

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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.