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Finding the Fourth Proportional to 428.05, 641.97 and 299.19

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Solution

The fourth proportional to 428.05, 641.97 and 299.19 is: 448.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.05 : 641.97 = 299.19 : x
  2. Step 2: Convert to fraction form
    428.05/641.97 = 299.19/x
  3. Step 3: Cross multiply
    428.05x = 641.97 × 299.19
  4. Step 4: Simplify right side
    428.05x = 192,071.00
  5. Step 5: Solve for x
    x = 192,071.00/428.05
  6. Step 6: Final answer
    x = 448.71

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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.