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Finding the Fourth Proportional to 680.20, 938.65 and 369.70

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Solution

The fourth proportional to 680.20, 938.65 and 369.70 is: 510.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.20 : 938.65 = 369.70 : x
  2. Step 2: Convert to fraction form
    680.20/938.65 = 369.70/x
  3. Step 3: Cross multiply
    680.20x = 938.65 × 369.70
  4. Step 4: Simplify right side
    680.20x = 347,018.91
  5. Step 5: Solve for x
    x = 347,018.91/680.20
  6. Step 6: Final answer
    x = 510.17

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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.