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Finding the Fourth Proportional to 30.11, 41.53 and 20.39

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Solution

The fourth proportional to 30.11, 41.53 and 20.39 is: 28.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.11 : 41.53 = 20.39 : x
  2. Step 2: Convert to fraction form
    30.11/41.53 = 20.39/x
  3. Step 3: Cross multiply
    30.11x = 41.53 × 20.39
  4. Step 4: Simplify right side
    30.11x = 846.80
  5. Step 5: Solve for x
    x = 846.80/30.11
  6. Step 6: Final answer
    x = 28.12

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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.