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Finding the Fourth Proportional to 643.89, 966.36 and 400.62

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Solution

The fourth proportional to 643.89, 966.36 and 400.62 is: 601.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.89 : 966.36 = 400.62 : x
  2. Step 2: Convert to fraction form
    643.89/966.36 = 400.62/x
  3. Step 3: Cross multiply
    643.89x = 966.36 × 400.62
  4. Step 4: Simplify right side
    643.89x = 387,143.14
  5. Step 5: Solve for x
    x = 387,143.14/643.89
  6. Step 6: Final answer
    x = 601.26

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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.