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Finding the Fourth Proportional to 22.15, 30.38 and 21.39

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Solution

The fourth proportional to 22.15, 30.38 and 21.39 is: 29.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    22.15 : 30.38 = 21.39 : x
  2. Step 2: Convert to fraction form
    22.15/30.38 = 21.39/x
  3. Step 3: Cross multiply
    22.15x = 30.38 × 21.39
  4. Step 4: Simplify right side
    22.15x = 649.61
  5. Step 5: Solve for x
    x = 649.61/22.15
  6. Step 6: Final answer
    x = 29.33

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.