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Finding the Fourth Proportional to 820.57, 1,229.88 and 300.15

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Solution

The fourth proportional to 820.57, 1,229.88 and 300.15 is: 449.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.57 : 1,229.88 = 300.15 : x
  2. Step 2: Convert to fraction form
    820.57/1,229.88 = 300.15/x
  3. Step 3: Cross multiply
    820.57x = 1,229.88 × 300.15
  4. Step 4: Simplify right side
    820.57x = 369,148.48
  5. Step 5: Solve for x
    x = 369,148.48/820.57
  6. Step 6: Final answer
    x = 449.87

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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.