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Finding the Fourth Proportional to 220.08, 330.30 and 81.30

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Solution

The fourth proportional to 220.08, 330.30 and 81.30 is: 122.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    220.08 : 330.30 = 81.30 : x
  2. Step 2: Convert to fraction form
    220.08/330.30 = 81.30/x
  3. Step 3: Cross multiply
    220.08x = 330.30 × 81.30
  4. Step 4: Simplify right side
    220.08x = 26,853.39
  5. Step 5: Solve for x
    x = 26,853.39/220.08
  6. Step 6: Final answer
    x = 122.02

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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.