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Finding the Fourth Proportional to 664.28, 995.05 and 389.71

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Solution

The fourth proportional to 664.28, 995.05 and 389.71 is: 583.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    664.28 : 995.05 = 389.71 : x
  2. Step 2: Convert to fraction form
    664.28/995.05 = 389.71/x
  3. Step 3: Cross multiply
    664.28x = 995.05 × 389.71
  4. Step 4: Simplify right side
    664.28x = 387,777.65
  5. Step 5: Solve for x
    x = 387,777.65/664.28
  6. Step 6: Final answer
    x = 583.76

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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.