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Finding the Fourth Proportional to 402.58, 603.87 and 257.86

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Solution

The fourth proportional to 402.58, 603.87 and 257.86 is: 386.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    402.58 : 603.87 = 257.86 : x
  2. Step 2: Convert to fraction form
    402.58/603.87 = 257.86/x
  3. Step 3: Cross multiply
    402.58x = 603.87 × 257.86
  4. Step 4: Simplify right side
    402.58x = 155,713.92
  5. Step 5: Solve for x
    x = 155,713.92/402.58
  6. Step 6: Final answer
    x = 386.79

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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.