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Finding the Fourth Proportional to 19.23, 28.85 and 7.21

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Solution

The fourth proportional to 19.23, 28.85 and 7.21 is: 10.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    19.23 : 28.85 = 7.21 : x
  2. Step 2: Convert to fraction form
    19.23/28.85 = 7.21/x
  3. Step 3: Cross multiply
    19.23x = 28.85 × 7.21
  4. Step 4: Simplify right side
    19.23x = 207.86
  5. Step 5: Solve for x
    x = 207.86/19.23
  6. Step 6: Final answer
    x = 10.81

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.