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Finding the Fourth Proportional to 399.87, 595.67 and 387.78

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Solution

The fourth proportional to 399.87, 595.67 and 387.78 is: 577.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.87 : 595.67 = 387.78 : x
  2. Step 2: Convert to fraction form
    399.87/595.67 = 387.78/x
  3. Step 3: Cross multiply
    399.87x = 595.67 × 387.78
  4. Step 4: Simplify right side
    399.87x = 230,989.88
  5. Step 5: Solve for x
    x = 230,989.88/399.87
  6. Step 6: Final answer
    x = 577.66

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.