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Finding the Fourth Proportional to 639.85, 883.49 and 499.73

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Solution

The fourth proportional to 639.85, 883.49 and 499.73 is: 690.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.85 : 883.49 = 499.73 : x
  2. Step 2: Convert to fraction form
    639.85/883.49 = 499.73/x
  3. Step 3: Cross multiply
    639.85x = 883.49 × 499.73
  4. Step 4: Simplify right side
    639.85x = 441,505.50
  5. Step 5: Solve for x
    x = 441,505.50/639.85
  6. Step 6: Final answer
    x = 690.01

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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.