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Finding the Fourth Proportional to 828.47, 1,239.29 and 680.56

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Solution

The fourth proportional to 828.47, 1,239.29 and 680.56 is: 1,018.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    828.47 : 1,239.29 = 680.56 : x
  2. Step 2: Convert to fraction form
    828.47/1,239.29 = 680.56/x
  3. Step 3: Cross multiply
    828.47x = 1,239.29 × 680.56
  4. Step 4: Simplify right side
    828.47x = 843,401.60
  5. Step 5: Solve for x
    x = 843,401.60/828.47
  6. Step 6: Final answer
    x = 1,018.02

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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.