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Finding the Fourth Proportional to 639.66, 883.83 and 509.70

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Solution

The fourth proportional to 639.66, 883.83 and 509.70 is: 704.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.66 : 883.83 = 509.70 : x
  2. Step 2: Convert to fraction form
    639.66/883.83 = 509.70/x
  3. Step 3: Cross multiply
    639.66x = 883.83 × 509.70
  4. Step 4: Simplify right side
    639.66x = 450,488.15
  5. Step 5: Solve for x
    x = 450,488.15/639.66
  6. Step 6: Final answer
    x = 704.26

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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.