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Finding the Fourth Proportional to 680.87, 939.62 and 386.15

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Solution

The fourth proportional to 680.87, 939.62 and 386.15 is: 532.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.87 : 939.62 = 386.15 : x
  2. Step 2: Convert to fraction form
    680.87/939.62 = 386.15/x
  3. Step 3: Cross multiply
    680.87x = 939.62 × 386.15
  4. Step 4: Simplify right side
    680.87x = 362,830.53
  5. Step 5: Solve for x
    x = 362,830.53/680.87
  6. Step 6: Final answer
    x = 532.89

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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.