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Finding the Fourth Proportional to 265.38, 397.90 and 128.30

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Solution

The fourth proportional to 265.38, 397.90 and 128.30 is: 192.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    265.38 : 397.90 = 128.30 : x
  2. Step 2: Convert to fraction form
    265.38/397.90 = 128.30/x
  3. Step 3: Cross multiply
    265.38x = 397.90 × 128.30
  4. Step 4: Simplify right side
    265.38x = 51,050.57
  5. Step 5: Solve for x
    x = 51,050.57/265.38
  6. Step 6: Final answer
    x = 192.37

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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.