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Finding the Fourth Proportional to 306.15, 422.31 and 207.72

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Solution

The fourth proportional to 306.15, 422.31 and 207.72 is: 286.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.15 : 422.31 = 207.72 : x
  2. Step 2: Convert to fraction form
    306.15/422.31 = 207.72/x
  3. Step 3: Cross multiply
    306.15x = 422.31 × 207.72
  4. Step 4: Simplify right side
    306.15x = 87,722.23
  5. Step 5: Solve for x
    x = 87,722.23/306.15
  6. Step 6: Final answer
    x = 286.53

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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.