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Finding the Fourth Proportional to 679.77, 938.10 and 385.05

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Solution

The fourth proportional to 679.77, 938.10 and 385.05 is: 531.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    679.77 : 938.10 = 385.05 : x
  2. Step 2: Convert to fraction form
    679.77/938.10 = 385.05/x
  3. Step 3: Cross multiply
    679.77x = 938.10 × 385.05
  4. Step 4: Simplify right side
    679.77x = 361,215.41
  5. Step 5: Solve for x
    x = 361,215.41/679.77
  6. Step 6: Final answer
    x = 531.38

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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.