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Finding the Fourth Proportional to 306.85, 422.79 and 208.44

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Solution

The fourth proportional to 306.85, 422.79 and 208.44 is: 287.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.85 : 422.79 = 208.44 : x
  2. Step 2: Convert to fraction form
    306.85/422.79 = 208.44/x
  3. Step 3: Cross multiply
    306.85x = 422.79 × 208.44
  4. Step 4: Simplify right side
    306.85x = 88,125.54
  5. Step 5: Solve for x
    x = 88,125.54/306.85
  6. Step 6: Final answer
    x = 287.19

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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.