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Finding the Fourth Proportional to 818.91, 1,228.67 and 380.38

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Solution

The fourth proportional to 818.91, 1,228.67 and 380.38 is: 570.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    818.91 : 1,228.67 = 380.38 : x
  2. Step 2: Convert to fraction form
    818.91/1,228.67 = 380.38/x
  3. Step 3: Cross multiply
    818.91x = 1,228.67 × 380.38
  4. Step 4: Simplify right side
    818.91x = 467,359.37
  5. Step 5: Solve for x
    x = 467,359.37/818.91
  6. Step 6: Final answer
    x = 570.71

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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.