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Finding the Fourth Proportional to 638.55, 957.31 and 394.56

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Solution

The fourth proportional to 638.55, 957.31 and 394.56 is: 591.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.55 : 957.31 = 394.56 : x
  2. Step 2: Convert to fraction form
    638.55/957.31 = 394.56/x
  3. Step 3: Cross multiply
    638.55x = 957.31 × 394.56
  4. Step 4: Simplify right side
    638.55x = 377,715.25
  5. Step 5: Solve for x
    x = 377,715.25/638.55
  6. Step 6: Final answer
    x = 591.52

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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.