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Finding the Fourth Proportional to 418.31, 628.68 and 388.13

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Solution

The fourth proportional to 418.31, 628.68 and 388.13 is: 583.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.31 : 628.68 = 388.13 : x
  2. Step 2: Convert to fraction form
    418.31/628.68 = 388.13/x
  3. Step 3: Cross multiply
    418.31x = 628.68 × 388.13
  4. Step 4: Simplify right side
    418.31x = 244,009.57
  5. Step 5: Solve for x
    x = 244,009.57/418.31
  6. Step 6: Final answer
    x = 583.32

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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.