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Finding the Fourth Proportional to 828.72, 1,243.28 and 308.75

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Solution

The fourth proportional to 828.72, 1,243.28 and 308.75 is: 463.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    828.72 : 1,243.28 = 308.75 : x
  2. Step 2: Convert to fraction form
    828.72/1,243.28 = 308.75/x
  3. Step 3: Cross multiply
    828.72x = 1,243.28 × 308.75
  4. Step 4: Simplify right side
    828.72x = 383,857.26
  5. Step 5: Solve for x
    x = 383,857.26/828.72
  6. Step 6: Final answer
    x = 463.19

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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.