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Finding the Fourth Proportional to 219.57, 329.26 and 128.30

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Solution

The fourth proportional to 219.57, 329.26 and 128.30 is: 192.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    219.57 : 329.26 = 128.30 : x
  2. Step 2: Convert to fraction form
    219.57/329.26 = 128.30/x
  3. Step 3: Cross multiply
    219.57x = 329.26 × 128.30
  4. Step 4: Simplify right side
    219.57x = 42,242.91
  5. Step 5: Solve for x
    x = 42,242.91/219.57
  6. Step 6: Final answer
    x = 192.39

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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.