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Finding the Fourth Proportional to 639.31, 957.10 and 395.09

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Solution

The fourth proportional to 639.31, 957.10 and 395.09 is: 591.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.31 : 957.10 = 395.09 : x
  2. Step 2: Convert to fraction form
    639.31/957.10 = 395.09/x
  3. Step 3: Cross multiply
    639.31x = 957.10 × 395.09
  4. Step 4: Simplify right side
    639.31x = 378,140.64
  5. Step 5: Solve for x
    x = 378,140.64/639.31
  6. Step 6: Final answer
    x = 591.48

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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.