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Finding the Fourth Proportional to 680.66, 939.30 and 385.98

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Solution

The fourth proportional to 680.66, 939.30 and 385.98 is: 532.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.66 : 939.30 = 385.98 : x
  2. Step 2: Convert to fraction form
    680.66/939.30 = 385.98/x
  3. Step 3: Cross multiply
    680.66x = 939.30 × 385.98
  4. Step 4: Simplify right side
    680.66x = 362,551.01
  5. Step 5: Solve for x
    x = 362,551.01/680.66
  6. Step 6: Final answer
    x = 532.65

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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.