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Finding the Fourth Proportional to 665.83, 998.69 and 421.82

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Solution

The fourth proportional to 665.83, 998.69 and 421.82 is: 632.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.83 : 998.69 = 421.82 : x
  2. Step 2: Convert to fraction form
    665.83/998.69 = 421.82/x
  3. Step 3: Cross multiply
    665.83x = 998.69 × 421.82
  4. Step 4: Simplify right side
    665.83x = 421,260.31
  5. Step 5: Solve for x
    x = 421,260.31/665.83
  6. Step 6: Final answer
    x = 632.69

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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.