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Finding the Fourth Proportional to 428.15, 641.84 and 154.18

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Solution

The fourth proportional to 428.15, 641.84 and 154.18 is: 231.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.15 : 641.84 = 154.18 : x
  2. Step 2: Convert to fraction form
    428.15/641.84 = 154.18/x
  3. Step 3: Cross multiply
    428.15x = 641.84 × 154.18
  4. Step 4: Simplify right side
    428.15x = 98,958.89
  5. Step 5: Solve for x
    x = 98,958.89/428.15
  6. Step 6: Final answer
    x = 231.13

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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.