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Finding the Fourth Proportional to 618.81, 928.10 and 207.89

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Solution

The fourth proportional to 618.81, 928.10 and 207.89 is: 311.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.81 : 928.10 = 207.89 : x
  2. Step 2: Convert to fraction form
    618.81/928.10 = 207.89/x
  3. Step 3: Cross multiply
    618.81x = 928.10 × 207.89
  4. Step 4: Simplify right side
    618.81x = 192,937.03
  5. Step 5: Solve for x
    x = 192,937.03/618.81
  6. Step 6: Final answer
    x = 311.79

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.