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Finding the Fourth Proportional to 618.70, 928.31 and 445.86

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Solution

The fourth proportional to 618.70, 928.31 and 445.86 is: 668.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.70 : 928.31 = 445.86 : x
  2. Step 2: Convert to fraction form
    618.70/928.31 = 445.86/x
  3. Step 3: Cross multiply
    618.70x = 928.31 × 445.86
  4. Step 4: Simplify right side
    618.70x = 413,896.30
  5. Step 5: Solve for x
    x = 413,896.30/618.70
  6. Step 6: Final answer
    x = 668.98

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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.