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Finding the Fourth Proportional to 28.70, 43.10 and 25.78

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Solution

The fourth proportional to 28.70, 43.10 and 25.78 is: 38.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.70 : 43.10 = 25.78 : x
  2. Step 2: Convert to fraction form
    28.70/43.10 = 25.78/x
  3. Step 3: Cross multiply
    28.70x = 43.10 × 25.78
  4. Step 4: Simplify right side
    28.70x = 1,111.12
  5. Step 5: Solve for x
    x = 1,111.12/28.70
  6. Step 6: Final answer
    x = 38.71

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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.