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Finding the Fourth Proportional to 15.22, 21.02 and 12.15

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Solution

The fourth proportional to 15.22, 21.02 and 12.15 is: 16.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    15.22 : 21.02 = 12.15 : x
  2. Step 2: Convert to fraction form
    15.22/21.02 = 12.15/x
  3. Step 3: Cross multiply
    15.22x = 21.02 × 12.15
  4. Step 4: Simplify right side
    15.22x = 255.39
  5. Step 5: Solve for x
    x = 255.39/15.22
  6. Step 6: Final answer
    x = 16.78

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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.