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Finding the Fourth Proportional to 666.30, 997.91 and 643.23

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Solution

The fourth proportional to 666.30, 997.91 and 643.23 is: 963.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.30 : 997.91 = 643.23 : x
  2. Step 2: Convert to fraction form
    666.30/997.91 = 643.23/x
  3. Step 3: Cross multiply
    666.30x = 997.91 × 643.23
  4. Step 4: Simplify right side
    666.30x = 641,882.43
  5. Step 5: Solve for x
    x = 641,882.43/666.30
  6. Step 6: Final answer
    x = 963.35

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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.