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Finding the Fourth Proportional to 515.91, 711.89 and 306.05

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Solution

The fourth proportional to 515.91, 711.89 and 306.05 is: 422.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    515.91 : 711.89 = 306.05 : x
  2. Step 2: Convert to fraction form
    515.91/711.89 = 306.05/x
  3. Step 3: Cross multiply
    515.91x = 711.89 × 306.05
  4. Step 4: Simplify right side
    515.91x = 217,874.18
  5. Step 5: Solve for x
    x = 217,874.18/515.91
  6. Step 6: Final answer
    x = 422.31

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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.