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Finding the Fourth Proportional to 220.40, 330.60 and 207.80

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Solution

The fourth proportional to 220.40, 330.60 and 207.80 is: 311.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    220.40 : 330.60 = 207.80 : x
  2. Step 2: Convert to fraction form
    220.40/330.60 = 207.80/x
  3. Step 3: Cross multiply
    220.40x = 330.60 × 207.80
  4. Step 4: Simplify right side
    220.40x = 68,698.68
  5. Step 5: Solve for x
    x = 68,698.68/220.40
  6. Step 6: Final answer
    x = 311.70

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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.