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Finding the Fourth Proportional to 805.38, 1,208.67 and 439.80

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Solution

The fourth proportional to 805.38, 1,208.67 and 439.80 is: 660.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    805.38 : 1,208.67 = 439.80 : x
  2. Step 2: Convert to fraction form
    805.38/1,208.67 = 439.80/x
  3. Step 3: Cross multiply
    805.38x = 1,208.67 × 439.80
  4. Step 4: Simplify right side
    805.38x = 531,573.07
  5. Step 5: Solve for x
    x = 531,573.07/805.38
  6. Step 6: Final answer
    x = 660.03

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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.