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Finding the Fourth Proportional to 34.28, 47.31 and 20.47

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Solution

The fourth proportional to 34.28, 47.31 and 20.47 is: 28.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    34.28 : 47.31 = 20.47 : x
  2. Step 2: Convert to fraction form
    34.28/47.31 = 20.47/x
  3. Step 3: Cross multiply
    34.28x = 47.31 × 20.47
  4. Step 4: Simplify right side
    34.28x = 968.33
  5. Step 5: Solve for x
    x = 968.33/34.28
  6. Step 6: Final answer
    x = 28.25

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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.