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Finding the Fourth Proportional to 839.69, 1,260.31 and 429.13

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Solution

The fourth proportional to 839.69, 1,260.31 and 429.13 is: 644.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    839.69 : 1,260.31 = 429.13 : x
  2. Step 2: Convert to fraction form
    839.69/1,260.31 = 429.13/x
  3. Step 3: Cross multiply
    839.69x = 1,260.31 × 429.13
  4. Step 4: Simplify right side
    839.69x = 540,836.83
  5. Step 5: Solve for x
    x = 540,836.83/839.69
  6. Step 6: Final answer
    x = 644.09

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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.