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Finding the Fourth Proportional to 428.29, 641.52 and 306.18

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Solution

The fourth proportional to 428.29, 641.52 and 306.18 is: 458.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.29 : 641.52 = 306.18 : x
  2. Step 2: Convert to fraction form
    428.29/641.52 = 306.18/x
  3. Step 3: Cross multiply
    428.29x = 641.52 × 306.18
  4. Step 4: Simplify right side
    428.29x = 196,420.59
  5. Step 5: Solve for x
    x = 196,420.59/428.29
  6. Step 6: Final answer
    x = 458.62

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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.