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Finding the Fourth Proportional to 408.21, 612.87 and 253.62

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Solution

The fourth proportional to 408.21, 612.87 and 253.62 is: 380.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    408.21 : 612.87 = 253.62 : x
  2. Step 2: Convert to fraction form
    408.21/612.87 = 253.62/x
  3. Step 3: Cross multiply
    408.21x = 612.87 × 253.62
  4. Step 4: Simplify right side
    408.21x = 155,436.09
  5. Step 5: Solve for x
    x = 155,436.09/408.21
  6. Step 6: Final answer
    x = 380.77

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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.