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Finding the Fourth Proportional to 205.29, 307.80 and 108.90

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Solution

The fourth proportional to 205.29, 307.80 and 108.90 is: 163.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.29 : 307.80 = 108.90 : x
  2. Step 2: Convert to fraction form
    205.29/307.80 = 108.90/x
  3. Step 3: Cross multiply
    205.29x = 307.80 × 108.90
  4. Step 4: Simplify right side
    205.29x = 33,519.42
  5. Step 5: Solve for x
    x = 33,519.42/205.29
  6. Step 6: Final answer
    x = 163.28

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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.