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Finding the Fourth Proportional to 679.93, 938.80 and 418.30

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Solution

The fourth proportional to 679.93, 938.80 and 418.30 is: 577.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    679.93 : 938.80 = 418.30 : x
  2. Step 2: Convert to fraction form
    679.93/938.80 = 418.30/x
  3. Step 3: Cross multiply
    679.93x = 938.80 × 418.30
  4. Step 4: Simplify right side
    679.93x = 392,700.04
  5. Step 5: Solve for x
    x = 392,700.04/679.93
  6. Step 6: Final answer
    x = 577.56

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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.