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Finding the Fourth Proportional to 809.40, 1,213.09 and 346.64

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Solution

The fourth proportional to 809.40, 1,213.09 and 346.64 is: 519.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    809.40 : 1,213.09 = 346.64 : x
  2. Step 2: Convert to fraction form
    809.40/1,213.09 = 346.64/x
  3. Step 3: Cross multiply
    809.40x = 1,213.09 × 346.64
  4. Step 4: Simplify right side
    809.40x = 420,497.72
  5. Step 5: Solve for x
    x = 420,497.72/809.40
  6. Step 6: Final answer
    x = 519.52

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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.