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Finding the Fourth Proportional to 28.65, 39.54 and 21.36

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Solution

The fourth proportional to 28.65, 39.54 and 21.36 is: 29.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.65 : 39.54 = 21.36 : x
  2. Step 2: Convert to fraction form
    28.65/39.54 = 21.36/x
  3. Step 3: Cross multiply
    28.65x = 39.54 × 21.36
  4. Step 4: Simplify right side
    28.65x = 844.57
  5. Step 5: Solve for x
    x = 844.57/28.65
  6. Step 6: Final answer
    x = 29.48

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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.