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Finding the Fourth Proportional to 428.42, 641.96 and 331.16

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Solution

The fourth proportional to 428.42, 641.96 and 331.16 is: 496.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.42 : 641.96 = 331.16 : x
  2. Step 2: Convert to fraction form
    428.42/641.96 = 331.16/x
  3. Step 3: Cross multiply
    428.42x = 641.96 × 331.16
  4. Step 4: Simplify right side
    428.42x = 212,588.49
  5. Step 5: Solve for x
    x = 212,588.49/428.42
  6. Step 6: Final answer
    x = 496.22

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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.