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Finding the Fourth Proportional to 77.88, 107.32 and 60.40

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Solution

The fourth proportional to 77.88, 107.32 and 60.40 is: 83.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.88 : 107.32 = 60.40 : x
  2. Step 2: Convert to fraction form
    77.88/107.32 = 60.40/x
  3. Step 3: Cross multiply
    77.88x = 107.32 × 60.40
  4. Step 4: Simplify right side
    77.88x = 6,481.29
  5. Step 5: Solve for x
    x = 6,481.29/77.88
  6. Step 6: Final answer
    x = 83.22

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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.