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Finding the Fourth Proportional to 820.36, 1,229.82 and 307.72

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Solution

The fourth proportional to 820.36, 1,229.82 and 307.72 is: 461.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.36 : 1,229.82 = 307.72 : x
  2. Step 2: Convert to fraction form
    820.36/1,229.82 = 307.72/x
  3. Step 3: Cross multiply
    820.36x = 1,229.82 × 307.72
  4. Step 4: Simplify right side
    820.36x = 378,440.21
  5. Step 5: Solve for x
    x = 378,440.21/820.36
  6. Step 6: Final answer
    x = 461.31

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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.