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Finding the Fourth Proportional to 28.89, 39.89 and 19.20

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Solution

The fourth proportional to 28.89, 39.89 and 19.20 is: 26.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.89 : 39.89 = 19.20 : x
  2. Step 2: Convert to fraction form
    28.89/39.89 = 19.20/x
  3. Step 3: Cross multiply
    28.89x = 39.89 × 19.20
  4. Step 4: Simplify right side
    28.89x = 766.09
  5. Step 5: Solve for x
    x = 766.09/28.89
  6. Step 6: Final answer
    x = 26.52

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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.