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Finding the Fourth Proportional to 228.20, 315.78 and 222.80

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Solution

The fourth proportional to 228.20, 315.78 and 222.80 is: 308.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    228.20 : 315.78 = 222.80 : x
  2. Step 2: Convert to fraction form
    228.20/315.78 = 222.80/x
  3. Step 3: Cross multiply
    228.20x = 315.78 × 222.80
  4. Step 4: Simplify right side
    228.20x = 70,355.78
  5. Step 5: Solve for x
    x = 70,355.78/228.20
  6. Step 6: Final answer
    x = 308.31

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.