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Finding the Fourth Proportional to 820.29, 1,231.05 and 455.19

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Solution

The fourth proportional to 820.29, 1,231.05 and 455.19 is: 683.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.29 : 1,231.05 = 455.19 : x
  2. Step 2: Convert to fraction form
    820.29/1,231.05 = 455.19/x
  3. Step 3: Cross multiply
    820.29x = 1,231.05 × 455.19
  4. Step 4: Simplify right side
    820.29x = 560,361.65
  5. Step 5: Solve for x
    x = 560,361.65/820.29
  6. Step 6: Final answer
    x = 683.13

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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.