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Finding the Fourth Proportional to 77.65, 107.08 and 71.77

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Solution

The fourth proportional to 77.65, 107.08 and 71.77 is: 98.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.65 : 107.08 = 71.77 : x
  2. Step 2: Convert to fraction form
    77.65/107.08 = 71.77/x
  3. Step 3: Cross multiply
    77.65x = 107.08 × 71.77
  4. Step 4: Simplify right side
    77.65x = 7,685.13
  5. Step 5: Solve for x
    x = 7,685.13/77.65
  6. Step 6: Final answer
    x = 98.97

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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.