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Finding the Fourth Proportional to 205.31, 307.85 and 68.31

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Solution

The fourth proportional to 205.31, 307.85 and 68.31 is: 102.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.31 : 307.85 = 68.31 : x
  2. Step 2: Convert to fraction form
    205.31/307.85 = 68.31/x
  3. Step 3: Cross multiply
    205.31x = 307.85 × 68.31
  4. Step 4: Simplify right side
    205.31x = 21,028.89
  5. Step 5: Solve for x
    x = 21,028.89/205.31
  6. Step 6: Final answer
    x = 102.43

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.