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Finding the Fourth Proportional to 809.23, 1,213.87 and 261.42

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Solution

The fourth proportional to 809.23, 1,213.87 and 261.42 is: 392.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    809.23 : 1,213.87 = 261.42 : x
  2. Step 2: Convert to fraction form
    809.23/1,213.87 = 261.42/x
  3. Step 3: Cross multiply
    809.23x = 1,213.87 × 261.42
  4. Step 4: Simplify right side
    809.23x = 317,323.83
  5. Step 5: Solve for x
    x = 317,323.83/809.23
  6. Step 6: Final answer
    x = 392.13

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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.