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Finding the Fourth Proportional to 639.12, 880.56 and 507.96

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Solution

The fourth proportional to 639.12, 880.56 and 507.96 is: 699.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.12 : 880.56 = 507.96 : x
  2. Step 2: Convert to fraction form
    639.12/880.56 = 507.96/x
  3. Step 3: Cross multiply
    639.12x = 880.56 × 507.96
  4. Step 4: Simplify right side
    639.12x = 447,289.26
  5. Step 5: Solve for x
    x = 447,289.26/639.12
  6. Step 6: Final answer
    x = 699.85

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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.