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Finding the Fourth Proportional to 665.78, 998.61 and 275.82

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Solution

The fourth proportional to 665.78, 998.61 and 275.82 is: 413.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.78 : 998.61 = 275.82 : x
  2. Step 2: Convert to fraction form
    665.78/998.61 = 275.82/x
  3. Step 3: Cross multiply
    665.78x = 998.61 × 275.82
  4. Step 4: Simplify right side
    665.78x = 275,436.61
  5. Step 5: Solve for x
    x = 275,436.61/665.78
  6. Step 6: Final answer
    x = 413.71

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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.