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Finding the Fourth Proportional to 641.77, 885.68 and 379.78

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Solution

The fourth proportional to 641.77, 885.68 and 379.78 is: 524.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.77 : 885.68 = 379.78 : x
  2. Step 2: Convert to fraction form
    641.77/885.68 = 379.78/x
  3. Step 3: Cross multiply
    641.77x = 885.68 × 379.78
  4. Step 4: Simplify right side
    641.77x = 336,363.55
  5. Step 5: Solve for x
    x = 336,363.55/641.77
  6. Step 6: Final answer
    x = 524.12

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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.