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Finding the Fourth Proportional to 641.75, 885.98 and 492.09

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Solution

The fourth proportional to 641.75, 885.98 and 492.09 is: 679.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.75 : 885.98 = 492.09 : x
  2. Step 2: Convert to fraction form
    641.75/885.98 = 492.09/x
  3. Step 3: Cross multiply
    641.75x = 885.98 × 492.09
  4. Step 4: Simplify right side
    641.75x = 435,979.44
  5. Step 5: Solve for x
    x = 435,979.44/641.75
  6. Step 6: Final answer
    x = 679.36

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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.