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Finding the Fourth Proportional to 686.08, 1,028.42 and 393.26

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Solution

The fourth proportional to 686.08, 1,028.42 and 393.26 is: 589.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.08 : 1,028.42 = 393.26 : x
  2. Step 2: Convert to fraction form
    686.08/1,028.42 = 393.26/x
  3. Step 3: Cross multiply
    686.08x = 1,028.42 × 393.26
  4. Step 4: Simplify right side
    686.08x = 404,437.05
  5. Step 5: Solve for x
    x = 404,437.05/686.08
  6. Step 6: Final answer
    x = 589.49

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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.