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Finding the Fourth Proportional to 428.12, 641.96 and 298.18

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Solution

The fourth proportional to 428.12, 641.96 and 298.18 is: 447.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.12 : 641.96 = 298.18 : x
  2. Step 2: Convert to fraction form
    428.12/641.96 = 298.18/x
  3. Step 3: Cross multiply
    428.12x = 641.96 × 298.18
  4. Step 4: Simplify right side
    428.12x = 191,418.77
  5. Step 5: Solve for x
    x = 191,418.77/428.12
  6. Step 6: Final answer
    x = 447.12

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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.