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Finding the Fourth Proportional to 647.31, 970.62 and 281.90

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Solution

The fourth proportional to 647.31, 970.62 and 281.90 is: 422.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.31 : 970.62 = 281.90 : x
  2. Step 2: Convert to fraction form
    647.31/970.62 = 281.90/x
  3. Step 3: Cross multiply
    647.31x = 970.62 × 281.90
  4. Step 4: Simplify right side
    647.31x = 273,620.73
  5. Step 5: Solve for x
    x = 273,620.73/647.31
  6. Step 6: Final answer
    x = 422.70

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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.