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Finding the Fourth Proportional to 641.78, 885.82 and 379.86

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Solution

The fourth proportional to 641.78, 885.82 and 379.86 is: 524.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.78 : 885.82 = 379.86 : x
  2. Step 2: Convert to fraction form
    641.78/885.82 = 379.86/x
  3. Step 3: Cross multiply
    641.78x = 885.82 × 379.86
  4. Step 4: Simplify right side
    641.78x = 336,487.59
  5. Step 5: Solve for x
    x = 336,487.59/641.78
  6. Step 6: Final answer
    x = 524.30

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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.