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Finding the Fourth Proportional to 679.59, 938.21 and 469.89

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Solution

The fourth proportional to 679.59, 938.21 and 469.89 is: 648.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    679.59 : 938.21 = 469.89 : x
  2. Step 2: Convert to fraction form
    679.59/938.21 = 469.89/x
  3. Step 3: Cross multiply
    679.59x = 938.21 × 469.89
  4. Step 4: Simplify right side
    679.59x = 440,853.15
  5. Step 5: Solve for x
    x = 440,853.15/679.59
  6. Step 6: Final answer
    x = 648.70

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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.