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Finding the Fourth Proportional to 397.72, 596.60 and 287.78

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Solution

The fourth proportional to 397.72, 596.60 and 287.78 is: 431.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    397.72 : 596.60 = 287.78 : x
  2. Step 2: Convert to fraction form
    397.72/596.60 = 287.78/x
  3. Step 3: Cross multiply
    397.72x = 596.60 × 287.78
  4. Step 4: Simplify right side
    397.72x = 171,689.55
  5. Step 5: Solve for x
    x = 171,689.55/397.72
  6. Step 6: Final answer
    x = 431.68

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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.