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Finding the Fourth Proportional to 659.31, 989.74 and 385.60

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Solution

The fourth proportional to 659.31, 989.74 and 385.60 is: 578.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.31 : 989.74 = 385.60 : x
  2. Step 2: Convert to fraction form
    659.31/989.74 = 385.60/x
  3. Step 3: Cross multiply
    659.31x = 989.74 × 385.60
  4. Step 4: Simplify right side
    659.31x = 381,644.22
  5. Step 5: Solve for x
    x = 381,644.22/659.31
  6. Step 6: Final answer
    x = 578.85

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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.