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Finding the Fourth Proportional to 680.52, 939 and 385.72

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Solution

The fourth proportional to 680.52, 939 and 385.72 is: 532.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.52 : 939 = 385.72 : x
  2. Step 2: Convert to fraction form
    680.52/939 = 385.72/x
  3. Step 3: Cross multiply
    680.52x = 939 × 385.72
  4. Step 4: Simplify right side
    680.52x = 362,191.08
  5. Step 5: Solve for x
    x = 362,191.08/680.52
  6. Step 6: Final answer
    x = 532.23

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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.