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Finding the Fourth Proportional to 438.58, 657.87 and 387.82

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Solution

The fourth proportional to 438.58, 657.87 and 387.82 is: 581.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.58 : 657.87 = 387.82 : x
  2. Step 2: Convert to fraction form
    438.58/657.87 = 387.82/x
  3. Step 3: Cross multiply
    438.58x = 657.87 × 387.82
  4. Step 4: Simplify right side
    438.58x = 255,135.14
  5. Step 5: Solve for x
    x = 255,135.14/438.58
  6. Step 6: Final answer
    x = 581.73

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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.