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Finding the Fourth Proportional to 828.93, 1,243.03 and 390.31

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Solution

The fourth proportional to 828.93, 1,243.03 and 390.31 is: 585.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    828.93 : 1,243.03 = 390.31 : x
  2. Step 2: Convert to fraction form
    828.93/1,243.03 = 390.31/x
  3. Step 3: Cross multiply
    828.93x = 1,243.03 × 390.31
  4. Step 4: Simplify right side
    828.93x = 485,160.82
  5. Step 5: Solve for x
    x = 485,160.82/828.93
  6. Step 6: Final answer
    x = 585.29

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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.