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Finding the Fourth Proportional to 428.70, 641.97 and 406.02

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Solution

The fourth proportional to 428.70, 641.97 and 406.02 is: 608.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.70 : 641.97 = 406.02 : x
  2. Step 2: Convert to fraction form
    428.70/641.97 = 406.02/x
  3. Step 3: Cross multiply
    428.70x = 641.97 × 406.02
  4. Step 4: Simplify right side
    428.70x = 260,652.66
  5. Step 5: Solve for x
    x = 260,652.66/428.70
  6. Step 6: Final answer
    x = 608.01

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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.