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Finding the Fourth Proportional to 386.12, 579.42 and 155.12

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Solution

The fourth proportional to 386.12, 579.42 and 155.12 is: 232.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.12 : 579.42 = 155.12 : x
  2. Step 2: Convert to fraction form
    386.12/579.42 = 155.12/x
  3. Step 3: Cross multiply
    386.12x = 579.42 × 155.12
  4. Step 4: Simplify right side
    386.12x = 89,879.63
  5. Step 5: Solve for x
    x = 89,879.63/386.12
  6. Step 6: Final answer
    x = 232.78

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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.