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Finding the Fourth Proportional to 639.21, 881.35 and 545.66

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Solution

The fourth proportional to 639.21, 881.35 and 545.66 is: 752.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.21 : 881.35 = 545.66 : x
  2. Step 2: Convert to fraction form
    639.21/881.35 = 545.66/x
  3. Step 3: Cross multiply
    639.21x = 881.35 × 545.66
  4. Step 4: Simplify right side
    639.21x = 480,917.44
  5. Step 5: Solve for x
    x = 480,917.44/639.21
  6. Step 6: Final answer
    x = 752.36

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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.