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Finding the Fourth Proportional to 71.39, 107.09 and 28.63

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Solution

The fourth proportional to 71.39, 107.09 and 28.63 is: 42.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.39 : 107.09 = 28.63 : x
  2. Step 2: Convert to fraction form
    71.39/107.09 = 28.63/x
  3. Step 3: Cross multiply
    71.39x = 107.09 × 28.63
  4. Step 4: Simplify right side
    71.39x = 3,065.45
  5. Step 5: Solve for x
    x = 3,065.45/71.39
  6. Step 6: Final answer
    x = 42.94

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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.