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Finding the Fourth Proportional to 820.09, 1,231.02 and 455.19

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Solution

The fourth proportional to 820.09, 1,231.02 and 455.19 is: 683.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.09 : 1,231.02 = 455.19 : x
  2. Step 2: Convert to fraction form
    820.09/1,231.02 = 455.19/x
  3. Step 3: Cross multiply
    820.09x = 1,231.02 × 455.19
  4. Step 4: Simplify right side
    820.09x = 560,339.56
  5. Step 5: Solve for x
    x = 560,339.56/820.09
  6. Step 6: Final answer
    x = 683.27

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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.