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Finding the Fourth Proportional to 679.45, 1,018.83 and 289.30

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Solution

The fourth proportional to 679.45, 1,018.83 and 289.30 is: 433.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    679.45 : 1,018.83 = 289.30 : x
  2. Step 2: Convert to fraction form
    679.45/1,018.83 = 289.30/x
  3. Step 3: Cross multiply
    679.45x = 1,018.83 × 289.30
  4. Step 4: Simplify right side
    679.45x = 294,747.52
  5. Step 5: Solve for x
    x = 294,747.52/679.45
  6. Step 6: Final answer
    x = 433.80

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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.