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Finding the Fourth Proportional to 77.72, 107.28 and 58.05

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Solution

The fourth proportional to 77.72, 107.28 and 58.05 is: 80.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.72 : 107.28 = 58.05 : x
  2. Step 2: Convert to fraction form
    77.72/107.28 = 58.05/x
  3. Step 3: Cross multiply
    77.72x = 107.28 × 58.05
  4. Step 4: Simplify right side
    77.72x = 6,227.60
  5. Step 5: Solve for x
    x = 6,227.60/77.72
  6. Step 6: Final answer
    x = 80.13

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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.