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Finding the Fourth Proportional to 665.90, 997.30 and 642.83

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Solution

The fourth proportional to 665.90, 997.30 and 642.83 is: 962.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.90 : 997.30 = 642.83 : x
  2. Step 2: Convert to fraction form
    665.90/997.30 = 642.83/x
  3. Step 3: Cross multiply
    665.90x = 997.30 × 642.83
  4. Step 4: Simplify right side
    665.90x = 641,087.77
  5. Step 5: Solve for x
    x = 641,087.77/665.90
  6. Step 6: Final answer
    x = 962.75

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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.