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Finding the Fourth Proportional to 642.43, 963.63 and 209.58

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Solution

The fourth proportional to 642.43, 963.63 and 209.58 is: 314.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.43 : 963.63 = 209.58 : x
  2. Step 2: Convert to fraction form
    642.43/963.63 = 209.58/x
  3. Step 3: Cross multiply
    642.43x = 963.63 × 209.58
  4. Step 4: Simplify right side
    642.43x = 201,957.58
  5. Step 5: Solve for x
    x = 201,957.58/642.43
  6. Step 6: Final answer
    x = 314.37

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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.