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Finding the Fourth Proportional to 392.39, 589.16 and 219.40

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Solution

The fourth proportional to 392.39, 589.16 and 219.40 is: 329.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    392.39 : 589.16 = 219.40 : x
  2. Step 2: Convert to fraction form
    392.39/589.16 = 219.40/x
  3. Step 3: Cross multiply
    392.39x = 589.16 × 219.40
  4. Step 4: Simplify right side
    392.39x = 129,261.70
  5. Step 5: Solve for x
    x = 129,261.70/392.39
  6. Step 6: Final answer
    x = 329.42

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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.