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Finding the Fourth Proportional to 380.85, 571.06 and 120.80

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Solution

The fourth proportional to 380.85, 571.06 and 120.80 is: 181.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.85 : 571.06 = 120.80 : x
  2. Step 2: Convert to fraction form
    380.85/571.06 = 120.80/x
  3. Step 3: Cross multiply
    380.85x = 571.06 × 120.80
  4. Step 4: Simplify right side
    380.85x = 68,982.54
  5. Step 5: Solve for x
    x = 68,982.54/380.85
  6. Step 6: Final answer
    x = 181.13

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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.