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Finding the Fourth Proportional to 399.03, 551.39 and 306.09

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Solution

The fourth proportional to 399.03, 551.39 and 306.09 is: 422.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.03 : 551.39 = 306.09 : x
  2. Step 2: Convert to fraction form
    399.03/551.39 = 306.09/x
  3. Step 3: Cross multiply
    399.03x = 551.39 × 306.09
  4. Step 4: Simplify right side
    399.03x = 168,774.97
  5. Step 5: Solve for x
    x = 168,774.97/399.03
  6. Step 6: Final answer
    x = 422.96

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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.