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Finding the Fourth Proportional to 807.58, 1,211.55 and 287.61

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Solution

The fourth proportional to 807.58, 1,211.55 and 287.61 is: 431.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.58 : 1,211.55 = 287.61 : x
  2. Step 2: Convert to fraction form
    807.58/1,211.55 = 287.61/x
  3. Step 3: Cross multiply
    807.58x = 1,211.55 × 287.61
  4. Step 4: Simplify right side
    807.58x = 348,453.90
  5. Step 5: Solve for x
    x = 348,453.90/807.58
  6. Step 6: Final answer
    x = 431.48

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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.