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Finding the Fourth Proportional to 639.15, 881.31 and 627.53

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Solution

The fourth proportional to 639.15, 881.31 and 627.53 is: 865.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.15 : 881.31 = 627.53 : x
  2. Step 2: Convert to fraction form
    639.15/881.31 = 627.53/x
  3. Step 3: Cross multiply
    639.15x = 881.31 × 627.53
  4. Step 4: Simplify right side
    639.15x = 553,044.06
  5. Step 5: Solve for x
    x = 553,044.06/639.15
  6. Step 6: Final answer
    x = 865.28

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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.