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Finding the Fourth Proportional to 679.85, 1,018.99 and 289.60

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Solution

The fourth proportional to 679.85, 1,018.99 and 289.60 is: 434.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    679.85 : 1,018.99 = 289.60 : x
  2. Step 2: Convert to fraction form
    679.85/1,018.99 = 289.60/x
  3. Step 3: Cross multiply
    679.85x = 1,018.99 × 289.60
  4. Step 4: Simplify right side
    679.85x = 295,099.50
  5. Step 5: Solve for x
    x = 295,099.50/679.85
  6. Step 6: Final answer
    x = 434.07

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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.