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Finding the Fourth Proportional to 28.72, 39.67 and 25.65

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Solution

The fourth proportional to 28.72, 39.67 and 25.65 is: 35.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.72 : 39.67 = 25.65 : x
  2. Step 2: Convert to fraction form
    28.72/39.67 = 25.65/x
  3. Step 3: Cross multiply
    28.72x = 39.67 × 25.65
  4. Step 4: Simplify right side
    28.72x = 1,017.41
  5. Step 5: Solve for x
    x = 1,017.41/28.72
  6. Step 6: Final answer
    x = 35.43

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.