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Finding the Fourth Proportional to 800.20, 1,105.41 and 775.90

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Solution

The fourth proportional to 800.20, 1,105.41 and 775.90 is: 1,071.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.20 : 1,105.41 = 775.90 : x
  2. Step 2: Convert to fraction form
    800.20/1,105.41 = 775.90/x
  3. Step 3: Cross multiply
    800.20x = 1,105.41 × 775.90
  4. Step 4: Simplify right side
    800.20x = 857,687.62
  5. Step 5: Solve for x
    x = 857,687.62/800.20
  6. Step 6: Final answer
    x = 1,071.84

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.