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Finding the Fourth Proportional to 415.87, 573.68 and 289.78

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Solution

The fourth proportional to 415.87, 573.68 and 289.78 is: 399.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    415.87 : 573.68 = 289.78 : x
  2. Step 2: Convert to fraction form
    415.87/573.68 = 289.78/x
  3. Step 3: Cross multiply
    415.87x = 573.68 × 289.78
  4. Step 4: Simplify right side
    415.87x = 166,240.28
  5. Step 5: Solve for x
    x = 166,240.28/415.87
  6. Step 6: Final answer
    x = 399.74

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.