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Finding the Fourth Proportional to 679.78, 938.33 and 556.80

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Solution

The fourth proportional to 679.78, 938.33 and 556.80 is: 768.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    679.78 : 938.33 = 556.80 : x
  2. Step 2: Convert to fraction form
    679.78/938.33 = 556.80/x
  3. Step 3: Cross multiply
    679.78x = 938.33 × 556.80
  4. Step 4: Simplify right side
    679.78x = 522,462.14
  5. Step 5: Solve for x
    x = 522,462.14/679.78
  6. Step 6: Final answer
    x = 768.58

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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.