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Finding the Fourth Proportional to 528.21, 791.49 and 219.80

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Solution

The fourth proportional to 528.21, 791.49 and 219.80 is: 329.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.21 : 791.49 = 219.80 : x
  2. Step 2: Convert to fraction form
    528.21/791.49 = 219.80/x
  3. Step 3: Cross multiply
    528.21x = 791.49 × 219.80
  4. Step 4: Simplify right side
    528.21x = 173,965.54
  5. Step 5: Solve for x
    x = 173,965.54/528.21
  6. Step 6: Final answer
    x = 329.35

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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.