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Finding the Fourth Proportional to 638.80, 958.38 and 227.98

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Solution

The fourth proportional to 638.80, 958.38 and 227.98 is: 342.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.80 : 958.38 = 227.98 : x
  2. Step 2: Convert to fraction form
    638.80/958.38 = 227.98/x
  3. Step 3: Cross multiply
    638.80x = 958.38 × 227.98
  4. Step 4: Simplify right side
    638.80x = 218,491.47
  5. Step 5: Solve for x
    x = 218,491.47/638.80
  6. Step 6: Final answer
    x = 342.03

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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.