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Finding the Fourth Proportional to 205.29, 308.04 and 128.28

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Solution

The fourth proportional to 205.29, 308.04 and 128.28 is: 192.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.29 : 308.04 = 128.28 : x
  2. Step 2: Convert to fraction form
    205.29/308.04 = 128.28/x
  3. Step 3: Cross multiply
    205.29x = 308.04 × 128.28
  4. Step 4: Simplify right side
    205.29x = 39,515.37
  5. Step 5: Solve for x
    x = 39,515.37/205.29
  6. Step 6: Final answer
    x = 192.49

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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.