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Finding the Fourth Proportional to 809.07, 1,213.63 and 261.26

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Solution

The fourth proportional to 809.07, 1,213.63 and 261.26 is: 391.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    809.07 : 1,213.63 = 261.26 : x
  2. Step 2: Convert to fraction form
    809.07/1,213.63 = 261.26/x
  3. Step 3: Cross multiply
    809.07x = 1,213.63 × 261.26
  4. Step 4: Simplify right side
    809.07x = 317,072.27
  5. Step 5: Solve for x
    x = 317,072.27/809.07
  6. Step 6: Final answer
    x = 391.90

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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.