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Finding the Fourth Proportional to 639.05, 880.21 and 635.27

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Solution

The fourth proportional to 639.05, 880.21 and 635.27 is: 875.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.05 : 880.21 = 635.27 : x
  2. Step 2: Convert to fraction form
    639.05/880.21 = 635.27/x
  3. Step 3: Cross multiply
    639.05x = 880.21 × 635.27
  4. Step 4: Simplify right side
    639.05x = 559,171.01
  5. Step 5: Solve for x
    x = 559,171.01/639.05
  6. Step 6: Final answer
    x = 875.00

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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.