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Finding the Fourth Proportional to 627.66, 865.86 and 378.81

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Solution

The fourth proportional to 627.66, 865.86 and 378.81 is: 522.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    627.66 : 865.86 = 378.81 : x
  2. Step 2: Convert to fraction form
    627.66/865.86 = 378.81/x
  3. Step 3: Cross multiply
    627.66x = 865.86 × 378.81
  4. Step 4: Simplify right side
    627.66x = 327,996.43
  5. Step 5: Solve for x
    x = 327,996.43/627.66
  6. Step 6: Final answer
    x = 522.57

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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.