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Finding the Fourth Proportional to 641.29, 961.95 and 208.39

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Solution

The fourth proportional to 641.29, 961.95 and 208.39 is: 312.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.29 : 961.95 = 208.39 : x
  2. Step 2: Convert to fraction form
    641.29/961.95 = 208.39/x
  3. Step 3: Cross multiply
    641.29x = 961.95 × 208.39
  4. Step 4: Simplify right side
    641.29x = 200,460.76
  5. Step 5: Solve for x
    x = 200,460.76/641.29
  6. Step 6: Final answer
    x = 312.59

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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.