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Finding the Fourth Proportional to 390.91, 540.03 and 331.80

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Solution

The fourth proportional to 390.91, 540.03 and 331.80 is: 458.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.91 : 540.03 = 331.80 : x
  2. Step 2: Convert to fraction form
    390.91/540.03 = 331.80/x
  3. Step 3: Cross multiply
    390.91x = 540.03 × 331.80
  4. Step 4: Simplify right side
    390.91x = 179,181.17
  5. Step 5: Solve for x
    x = 179,181.17/390.91
  6. Step 6: Final answer
    x = 458.37

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.