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Finding the Fourth Proportional to 807.60, 1,211.28 and 259.83

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Solution

The fourth proportional to 807.60, 1,211.28 and 259.83 is: 389.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.60 : 1,211.28 = 259.83 : x
  2. Step 2: Convert to fraction form
    807.60/1,211.28 = 259.83/x
  3. Step 3: Cross multiply
    807.60x = 1,211.28 × 259.83
  4. Step 4: Simplify right side
    807.60x = 314,726.88
  5. Step 5: Solve for x
    x = 314,726.88/807.60
  6. Step 6: Final answer
    x = 389.71

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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.