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Finding the Fourth Proportional to 428.09, 641.12 and 245.03

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Solution

The fourth proportional to 428.09, 641.12 and 245.03 is: 366.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.09 : 641.12 = 245.03 : x
  2. Step 2: Convert to fraction form
    428.09/641.12 = 245.03/x
  3. Step 3: Cross multiply
    428.09x = 641.12 × 245.03
  4. Step 4: Simplify right side
    428.09x = 157,089.20
  5. Step 5: Solve for x
    x = 157,089.20/428.09
  6. Step 6: Final answer
    x = 366.96

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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.