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Finding the Fourth Proportional to 641.22, 961.87 and 208.38

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Solution

The fourth proportional to 641.22, 961.87 and 208.38 is: 312.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.22 : 961.87 = 208.38 : x
  2. Step 2: Convert to fraction form
    641.22/961.87 = 208.38/x
  3. Step 3: Cross multiply
    641.22x = 961.87 × 208.38
  4. Step 4: Simplify right side
    641.22x = 200,434.47
  5. Step 5: Solve for x
    x = 200,434.47/641.22
  6. Step 6: Final answer
    x = 312.58

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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.