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Finding the Fourth Proportional to 618.81, 928.47 and 345.09

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Solution

The fourth proportional to 618.81, 928.47 and 345.09 is: 517.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.81 : 928.47 = 345.09 : x
  2. Step 2: Convert to fraction form
    618.81/928.47 = 345.09/x
  3. Step 3: Cross multiply
    618.81x = 928.47 × 345.09
  4. Step 4: Simplify right side
    618.81x = 320,405.71
  5. Step 5: Solve for x
    x = 320,405.71/618.81
  6. Step 6: Final answer
    x = 517.78

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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.