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Finding the Fourth Proportional to 660.82, 911.87 and 380.99

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Solution

The fourth proportional to 660.82, 911.87 and 380.99 is: 525.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.82 : 911.87 = 380.99 : x
  2. Step 2: Convert to fraction form
    660.82/911.87 = 380.99/x
  3. Step 3: Cross multiply
    660.82x = 911.87 × 380.99
  4. Step 4: Simplify right side
    660.82x = 347,413.35
  5. Step 5: Solve for x
    x = 347,413.35/660.82
  6. Step 6: Final answer
    x = 525.73

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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.