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Finding the Fourth Proportional to 679.99, 938.42 and 418.09

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Solution

The fourth proportional to 679.99, 938.42 and 418.09 is: 576.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    679.99 : 938.42 = 418.09 : x
  2. Step 2: Convert to fraction form
    679.99/938.42 = 418.09/x
  3. Step 3: Cross multiply
    679.99x = 938.42 × 418.09
  4. Step 4: Simplify right side
    679.99x = 392,344.02
  5. Step 5: Solve for x
    x = 392,344.02/679.99
  6. Step 6: Final answer
    x = 576.98

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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.