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Finding the Fourth Proportional to 286.38, 429.31 and 138.05

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Solution

The fourth proportional to 286.38, 429.31 and 138.05 is: 206.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    286.38 : 429.31 = 138.05 : x
  2. Step 2: Convert to fraction form
    286.38/429.31 = 138.05/x
  3. Step 3: Cross multiply
    286.38x = 429.31 × 138.05
  4. Step 4: Simplify right side
    286.38x = 59,263.75
  5. Step 5: Solve for x
    x = 59,263.75/286.38
  6. Step 6: Final answer
    x = 206.94

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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.