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Finding the Fourth Proportional to 800.62, 1,200.78 and 215.65

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Solution

The fourth proportional to 800.62, 1,200.78 and 215.65 is: 323.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.62 : 1,200.78 = 215.65 : x
  2. Step 2: Convert to fraction form
    800.62/1,200.78 = 215.65/x
  3. Step 3: Cross multiply
    800.62x = 1,200.78 × 215.65
  4. Step 4: Simplify right side
    800.62x = 258,950.31
  5. Step 5: Solve for x
    x = 258,950.31/800.62
  6. Step 6: Final answer
    x = 323.44

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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.