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Finding the Fourth Proportional to 839, 1,257.96 and 290.90

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Solution

The fourth proportional to 839, 1,257.96 and 290.90 is: 436.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    839 : 1,257.96 = 290.90 : x
  2. Step 2: Convert to fraction form
    839/1,257.96 = 290.90/x
  3. Step 3: Cross multiply
    839x = 1,257.96 × 290.90
  4. Step 4: Simplify right side
    839x = 365,940.56
  5. Step 5: Solve for x
    x = 365,940.56/839
  6. Step 6: Final answer
    x = 436.16

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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.