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Finding the Fourth Proportional to 639.75, 883.14 and 490.41

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Solution

The fourth proportional to 639.75, 883.14 and 490.41 is: 676.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.75 : 883.14 = 490.41 : x
  2. Step 2: Convert to fraction form
    639.75/883.14 = 490.41/x
  3. Step 3: Cross multiply
    639.75x = 883.14 × 490.41
  4. Step 4: Simplify right side
    639.75x = 433,100.69
  5. Step 5: Solve for x
    x = 433,100.69/639.75
  6. Step 6: Final answer
    x = 676.98

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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.