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Finding the Fourth Proportional to 618.69, 928.08 and 207.80

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Solution

The fourth proportional to 618.69, 928.08 and 207.80 is: 311.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.69 : 928.08 = 207.80 : x
  2. Step 2: Convert to fraction form
    618.69/928.08 = 207.80/x
  3. Step 3: Cross multiply
    618.69x = 928.08 × 207.80
  4. Step 4: Simplify right side
    618.69x = 192,849.34
  5. Step 5: Solve for x
    x = 192,849.34/618.69
  6. Step 6: Final answer
    x = 311.71

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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.