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Finding the Fourth Proportional to 807.69, 1,211.28 and 259.75

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Solution

The fourth proportional to 807.69, 1,211.28 and 259.75 is: 389.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.69 : 1,211.28 = 259.75 : x
  2. Step 2: Convert to fraction form
    807.69/1,211.28 = 259.75/x
  3. Step 3: Cross multiply
    807.69x = 1,211.28 × 259.75
  4. Step 4: Simplify right side
    807.69x = 314,629.98
  5. Step 5: Solve for x
    x = 314,629.98/807.69
  6. Step 6: Final answer
    x = 389.54

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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.