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Finding the Fourth Proportional to 641.25, 961.90 and 275.79

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Solution

The fourth proportional to 641.25, 961.90 and 275.79 is: 413.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.25 : 961.90 = 275.79 : x
  2. Step 2: Convert to fraction form
    641.25/961.90 = 275.79/x
  3. Step 3: Cross multiply
    641.25x = 961.90 × 275.79
  4. Step 4: Simplify right side
    641.25x = 265,282.40
  5. Step 5: Solve for x
    x = 265,282.40/641.25
  6. Step 6: Final answer
    x = 413.70

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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.