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Finding the Fourth Proportional to 76.76, 115.08 and 54.80

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Solution

The fourth proportional to 76.76, 115.08 and 54.80 is: 82.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    76.76 : 115.08 = 54.80 : x
  2. Step 2: Convert to fraction form
    76.76/115.08 = 54.80/x
  3. Step 3: Cross multiply
    76.76x = 115.08 × 54.80
  4. Step 4: Simplify right side
    76.76x = 6,306.38
  5. Step 5: Solve for x
    x = 6,306.38/76.76
  6. Step 6: Final answer
    x = 82.16

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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.