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Finding the Fourth Proportional to 502.78, 693.90 and 306.28

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Solution

The fourth proportional to 502.78, 693.90 and 306.28 is: 422.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    502.78 : 693.90 = 306.28 : x
  2. Step 2: Convert to fraction form
    502.78/693.90 = 306.28/x
  3. Step 3: Cross multiply
    502.78x = 693.90 × 306.28
  4. Step 4: Simplify right side
    502.78x = 212,527.69
  5. Step 5: Solve for x
    x = 212,527.69/502.78
  6. Step 6: Final answer
    x = 422.71

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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.