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Finding the Fourth Proportional to 828.85, 1,243.92 and 439.31

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Solution

The fourth proportional to 828.85, 1,243.92 and 439.31 is: 659.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    828.85 : 1,243.92 = 439.31 : x
  2. Step 2: Convert to fraction form
    828.85/1,243.92 = 439.31/x
  3. Step 3: Cross multiply
    828.85x = 1,243.92 × 439.31
  4. Step 4: Simplify right side
    828.85x = 546,466.50
  5. Step 5: Solve for x
    x = 546,466.50/828.85
  6. Step 6: Final answer
    x = 659.31

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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.