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Finding the Fourth Proportional to 71.58, 107.38 and 20.22

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Solution

The fourth proportional to 71.58, 107.38 and 20.22 is: 30.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.58 : 107.38 = 20.22 : x
  2. Step 2: Convert to fraction form
    71.58/107.38 = 20.22/x
  3. Step 3: Cross multiply
    71.58x = 107.38 × 20.22
  4. Step 4: Simplify right side
    71.58x = 2,171.54
  5. Step 5: Solve for x
    x = 2,171.54/71.58
  6. Step 6: Final answer
    x = 30.34

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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.