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Finding the Fourth Proportional to 641.85, 962.13 and 208.71

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Solution

The fourth proportional to 641.85, 962.13 and 208.71 is: 312.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.85 : 962.13 = 208.71 : x
  2. Step 2: Convert to fraction form
    641.85/962.13 = 208.71/x
  3. Step 3: Cross multiply
    641.85x = 962.13 × 208.71
  4. Step 4: Simplify right side
    641.85x = 200,806.15
  5. Step 5: Solve for x
    x = 200,806.15/641.85
  6. Step 6: Final answer
    x = 312.86

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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.