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Finding the Fourth Proportional to 642.83, 963.92 and 209.93

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Solution

The fourth proportional to 642.83, 963.92 and 209.93 is: 314.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.83 : 963.92 = 209.93 : x
  2. Step 2: Convert to fraction form
    642.83/963.92 = 209.93/x
  3. Step 3: Cross multiply
    642.83x = 963.92 × 209.93
  4. Step 4: Simplify right side
    642.83x = 202,349.86
  5. Step 5: Solve for x
    x = 202,349.86/642.83
  6. Step 6: Final answer
    x = 314.78

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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.