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Finding the Fourth Proportional to 408.54, 612.80 and 213.06

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Solution

The fourth proportional to 408.54, 612.80 and 213.06 is: 319.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    408.54 : 612.80 = 213.06 : x
  2. Step 2: Convert to fraction form
    408.54/612.80 = 213.06/x
  3. Step 3: Cross multiply
    408.54x = 612.80 × 213.06
  4. Step 4: Simplify right side
    408.54x = 130,563.17
  5. Step 5: Solve for x
    x = 130,563.17/408.54
  6. Step 6: Final answer
    x = 319.58

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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.