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Finding the Fourth Proportional to 265.50, 397.86 and 128.38

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Solution

The fourth proportional to 265.50, 397.86 and 128.38 is: 192.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    265.50 : 397.86 = 128.38 : x
  2. Step 2: Convert to fraction form
    265.50/397.86 = 128.38/x
  3. Step 3: Cross multiply
    265.50x = 397.86 × 128.38
  4. Step 4: Simplify right side
    265.50x = 51,076.62
  5. Step 5: Solve for x
    x = 51,076.62/265.50
  6. Step 6: Final answer
    x = 192.38

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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.