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Finding the Fourth Proportional to 205.85, 308.76 and 68.90

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Solution

The fourth proportional to 205.85, 308.76 and 68.90 is: 103.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.85 : 308.76 = 68.90 : x
  2. Step 2: Convert to fraction form
    205.85/308.76 = 68.90/x
  3. Step 3: Cross multiply
    205.85x = 308.76 × 68.90
  4. Step 4: Simplify right side
    205.85x = 21,272.02
  5. Step 5: Solve for x
    x = 21,272.02/205.85
  6. Step 6: Final answer
    x = 103.34

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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.