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Finding the Fourth Proportional to 645.33, 965.60 and 385.47

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Solution

The fourth proportional to 645.33, 965.60 and 385.47 is: 576.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.33 : 965.60 = 385.47 : x
  2. Step 2: Convert to fraction form
    645.33/965.60 = 385.47/x
  3. Step 3: Cross multiply
    645.33x = 965.60 × 385.47
  4. Step 4: Simplify right side
    645.33x = 372,212.79
  5. Step 5: Solve for x
    x = 372,212.79/645.33
  6. Step 6: Final answer
    x = 576.78

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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.