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Finding the Fourth Proportional to 200.94, 300.78 and 128.85

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Solution

The fourth proportional to 200.94, 300.78 and 128.85 is: 192.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    200.94 : 300.78 = 128.85 : x
  2. Step 2: Convert to fraction form
    200.94/300.78 = 128.85/x
  3. Step 3: Cross multiply
    200.94x = 300.78 × 128.85
  4. Step 4: Simplify right side
    200.94x = 38,755.50
  5. Step 5: Solve for x
    x = 38,755.50/200.94
  6. Step 6: Final answer
    x = 192.87

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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.