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Finding the Fourth Proportional to 380.12, 523.30 and 281.70

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Solution

The fourth proportional to 380.12, 523.30 and 281.70 is: 387.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.12 : 523.30 = 281.70 : x
  2. Step 2: Convert to fraction form
    380.12/523.30 = 281.70/x
  3. Step 3: Cross multiply
    380.12x = 523.30 × 281.70
  4. Step 4: Simplify right side
    380.12x = 147,413.61
  5. Step 5: Solve for x
    x = 147,413.61/380.12
  6. Step 6: Final answer
    x = 387.81

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.