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Finding the Fourth Proportional to 428.40, 591.47 and 281.30

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Solution

The fourth proportional to 428.40, 591.47 and 281.30 is: 388.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.40 : 591.47 = 281.30 : x
  2. Step 2: Convert to fraction form
    428.40/591.47 = 281.30/x
  3. Step 3: Cross multiply
    428.40x = 591.47 × 281.30
  4. Step 4: Simplify right side
    428.40x = 166,376.15
  5. Step 5: Solve for x
    x = 166,376.15/428.40
  6. Step 6: Final answer
    x = 388.37

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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.