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Finding the Fourth Proportional to 641.79, 961.38 and 519.75

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Solution

The fourth proportional to 641.79, 961.38 and 519.75 is: 778.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.79 : 961.38 = 519.75 : x
  2. Step 2: Convert to fraction form
    641.79/961.38 = 519.75/x
  3. Step 3: Cross multiply
    641.79x = 961.38 × 519.75
  4. Step 4: Simplify right side
    641.79x = 499,677.26
  5. Step 5: Solve for x
    x = 499,677.26/641.79
  6. Step 6: Final answer
    x = 778.57

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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.