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Finding the Fourth Proportional to 286.15, 396.55 and 280.68

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Solution

The fourth proportional to 286.15, 396.55 and 280.68 is: 388.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    286.15 : 396.55 = 280.68 : x
  2. Step 2: Convert to fraction form
    286.15/396.55 = 280.68/x
  3. Step 3: Cross multiply
    286.15x = 396.55 × 280.68
  4. Step 4: Simplify right side
    286.15x = 111,303.65
  5. Step 5: Solve for x
    x = 111,303.65/286.15
  6. Step 6: Final answer
    x = 388.97

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.