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Finding the Fourth Proportional to 818.94, 1,228.80 and 408.11

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Solution

The fourth proportional to 818.94, 1,228.80 and 408.11 is: 612.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    818.94 : 1,228.80 = 408.11 : x
  2. Step 2: Convert to fraction form
    818.94/1,228.80 = 408.11/x
  3. Step 3: Cross multiply
    818.94x = 1,228.80 × 408.11
  4. Step 4: Simplify right side
    818.94x = 501,485.57
  5. Step 5: Solve for x
    x = 501,485.57/818.94
  6. Step 6: Final answer
    x = 612.36

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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.