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Finding the Fourth Proportional to 306.31, 422.55 and 208.09

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Solution

The fourth proportional to 306.31, 422.55 and 208.09 is: 287.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.31 : 422.55 = 208.09 : x
  2. Step 2: Convert to fraction form
    306.31/422.55 = 208.09/x
  3. Step 3: Cross multiply
    306.31x = 422.55 × 208.09
  4. Step 4: Simplify right side
    306.31x = 87,928.43
  5. Step 5: Solve for x
    x = 87,928.43/306.31
  6. Step 6: Final answer
    x = 287.06

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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.