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Finding the Fourth Proportional to 698.20, 963.49 and 387.70

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Solution

The fourth proportional to 698.20, 963.49 and 387.70 is: 535.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    698.20 : 963.49 = 387.70 : x
  2. Step 2: Convert to fraction form
    698.20/963.49 = 387.70/x
  3. Step 3: Cross multiply
    698.20x = 963.49 × 387.70
  4. Step 4: Simplify right side
    698.20x = 373,545.07
  5. Step 5: Solve for x
    x = 373,545.07/698.20
  6. Step 6: Final answer
    x = 535.01

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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.