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Finding the Fourth Proportional to 680.59, 939.32 and 385.89

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Solution

The fourth proportional to 680.59, 939.32 and 385.89 is: 532.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.59 : 939.32 = 385.89 : x
  2. Step 2: Convert to fraction form
    680.59/939.32 = 385.89/x
  3. Step 3: Cross multiply
    680.59x = 939.32 × 385.89
  4. Step 4: Simplify right side
    680.59x = 362,474.19
  5. Step 5: Solve for x
    x = 362,474.19/680.59
  6. Step 6: Final answer
    x = 532.59

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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.