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Finding the Fourth Proportional to 665.31, 998.37 and 280.56

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Solution

The fourth proportional to 665.31, 998.37 and 280.56 is: 421.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.31 : 998.37 = 280.56 : x
  2. Step 2: Convert to fraction form
    665.31/998.37 = 280.56/x
  3. Step 3: Cross multiply
    665.31x = 998.37 × 280.56
  4. Step 4: Simplify right side
    665.31x = 280,102.69
  5. Step 5: Solve for x
    x = 280,102.69/665.31
  6. Step 6: Final answer
    x = 421.01

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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.