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Finding the Fourth Proportional to 664.05, 994.71 and 389.31

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Solution

The fourth proportional to 664.05, 994.71 and 389.31 is: 583.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    664.05 : 994.71 = 389.31 : x
  2. Step 2: Convert to fraction form
    664.05/994.71 = 389.31/x
  3. Step 3: Cross multiply
    664.05x = 994.71 × 389.31
  4. Step 4: Simplify right side
    664.05x = 387,250.55
  5. Step 5: Solve for x
    x = 387,250.55/664.05
  6. Step 6: Final answer
    x = 583.16

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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.