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Finding the Fourth Proportional to 820.58, 1,228.98 and 408.44

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Solution

The fourth proportional to 820.58, 1,228.98 and 408.44 is: 611.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.58 : 1,228.98 = 408.44 : x
  2. Step 2: Convert to fraction form
    820.58/1,228.98 = 408.44/x
  3. Step 3: Cross multiply
    820.58x = 1,228.98 × 408.44
  4. Step 4: Simplify right side
    820.58x = 501,964.59
  5. Step 5: Solve for x
    x = 501,964.59/820.58
  6. Step 6: Final answer
    x = 611.72

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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.