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Finding the Fourth Proportional to 205.21, 307.91 and 109

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Solution

The fourth proportional to 205.21, 307.91 and 109 is: 163.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.21 : 307.91 = 109 : x
  2. Step 2: Convert to fraction form
    205.21/307.91 = 109/x
  3. Step 3: Cross multiply
    205.21x = 307.91 × 109
  4. Step 4: Simplify right side
    205.21x = 33,562.19
  5. Step 5: Solve for x
    x = 33,562.19/205.21
  6. Step 6: Final answer
    x = 163.55

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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.