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Finding the Fourth Proportional to 418.05, 628.10 and 393.45

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Solution

The fourth proportional to 418.05, 628.10 and 393.45 is: 591.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.05 : 628.10 = 393.45 : x
  2. Step 2: Convert to fraction form
    418.05/628.10 = 393.45/x
  3. Step 3: Cross multiply
    418.05x = 628.10 × 393.45
  4. Step 4: Simplify right side
    418.05x = 247,125.95
  5. Step 5: Solve for x
    x = 247,125.95/418.05
  6. Step 6: Final answer
    x = 591.14

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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.