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Finding the Fourth Proportional to 227.20, 342.40 and 212.80

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Solution

The fourth proportional to 227.20, 342.40 and 212.80 is: 320.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    227.20 : 342.40 = 212.80 : x
  2. Step 2: Convert to fraction form
    227.20/342.40 = 212.80/x
  3. Step 3: Cross multiply
    227.20x = 342.40 × 212.80
  4. Step 4: Simplify right side
    227.20x = 72,862.72
  5. Step 5: Solve for x
    x = 72,862.72/227.20
  6. Step 6: Final answer
    x = 320.70

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.