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Finding the Fourth Proportional to 420.36, 579.87 and 393.03

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Solution

The fourth proportional to 420.36, 579.87 and 393.03 is: 542.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.36 : 579.87 = 393.03 : x
  2. Step 2: Convert to fraction form
    420.36/579.87 = 393.03/x
  3. Step 3: Cross multiply
    420.36x = 579.87 × 393.03
  4. Step 4: Simplify right side
    420.36x = 227,906.31
  5. Step 5: Solve for x
    x = 227,906.31/420.36
  6. Step 6: Final answer
    x = 542.17

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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.