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Finding the Fourth Proportional to 642.37, 963.42 and 209.65

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Solution

The fourth proportional to 642.37, 963.42 and 209.65 is: 314.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.37 : 963.42 = 209.65 : x
  2. Step 2: Convert to fraction form
    642.37/963.42 = 209.65/x
  3. Step 3: Cross multiply
    642.37x = 963.42 × 209.65
  4. Step 4: Simplify right side
    642.37x = 201,981.00
  5. Step 5: Solve for x
    x = 201,981.00/642.37
  6. Step 6: Final answer
    x = 314.43

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.