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Finding the Fourth Proportional to 720.83, 1,081.21 and 200.86

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Solution

The fourth proportional to 720.83, 1,081.21 and 200.86 is: 301.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.83 : 1,081.21 = 200.86 : x
  2. Step 2: Convert to fraction form
    720.83/1,081.21 = 200.86/x
  3. Step 3: Cross multiply
    720.83x = 1,081.21 × 200.86
  4. Step 4: Simplify right side
    720.83x = 217,174.53
  5. Step 5: Solve for x
    x = 217,174.53/720.83
  6. Step 6: Final answer
    x = 301.28

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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.