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Finding the Fourth Proportional to 428.68, 641.69 and 330.93

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Solution

The fourth proportional to 428.68, 641.69 and 330.93 is: 495.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.68 : 641.69 = 330.93 : x
  2. Step 2: Convert to fraction form
    428.68/641.69 = 330.93/x
  3. Step 3: Cross multiply
    428.68x = 641.69 × 330.93
  4. Step 4: Simplify right side
    428.68x = 212,354.47
  5. Step 5: Solve for x
    x = 212,354.47/428.68
  6. Step 6: Final answer
    x = 495.37

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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.