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Finding the Fourth Proportional to 642.25, 963.39 and 209.41

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Solution

The fourth proportional to 642.25, 963.39 and 209.41 is: 314.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.25 : 963.39 = 209.41 : x
  2. Step 2: Convert to fraction form
    642.25/963.39 = 209.41/x
  3. Step 3: Cross multiply
    642.25x = 963.39 × 209.41
  4. Step 4: Simplify right side
    642.25x = 201,743.50
  5. Step 5: Solve for x
    x = 201,743.50/642.25
  6. Step 6: Final answer
    x = 314.12

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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.