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Finding the Fourth Proportional to 428.45, 591.30 and 281.12

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Solution

The fourth proportional to 428.45, 591.30 and 281.12 is: 387.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.45 : 591.30 = 281.12 : x
  2. Step 2: Convert to fraction form
    428.45/591.30 = 281.12/x
  3. Step 3: Cross multiply
    428.45x = 591.30 × 281.12
  4. Step 4: Simplify right side
    428.45x = 166,223.30
  5. Step 5: Solve for x
    x = 166,223.30/428.45
  6. Step 6: Final answer
    x = 387.97

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.