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Finding the Fourth Proportional to 77.86, 107.51 and 54.55

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Solution

The fourth proportional to 77.86, 107.51 and 54.55 is: 75.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.86 : 107.51 = 54.55 : x
  2. Step 2: Convert to fraction form
    77.86/107.51 = 54.55/x
  3. Step 3: Cross multiply
    77.86x = 107.51 × 54.55
  4. Step 4: Simplify right side
    77.86x = 5,864.67
  5. Step 5: Solve for x
    x = 5,864.67/77.86
  6. Step 6: Final answer
    x = 75.32

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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.