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Finding the Fourth Proportional to 408.39, 612.68 and 130.77

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Solution

The fourth proportional to 408.39, 612.68 and 130.77 is: 196.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    408.39 : 612.68 = 130.77 : x
  2. Step 2: Convert to fraction form
    408.39/612.68 = 130.77/x
  3. Step 3: Cross multiply
    408.39x = 612.68 × 130.77
  4. Step 4: Simplify right side
    408.39x = 80,119.51
  5. Step 5: Solve for x
    x = 80,119.51/408.39
  6. Step 6: Final answer
    x = 196.18

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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.