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Finding the Fourth Proportional to 203.80, 305.71 and 66.85

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Solution

The fourth proportional to 203.80, 305.71 and 66.85 is: 100.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    203.80 : 305.71 = 66.85 : x
  2. Step 2: Convert to fraction form
    203.80/305.71 = 66.85/x
  3. Step 3: Cross multiply
    203.80x = 305.71 × 66.85
  4. Step 4: Simplify right side
    203.80x = 20,435.02
  5. Step 5: Solve for x
    x = 20,435.02/203.80
  6. Step 6: Final answer
    x = 100.27

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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.