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Finding the Fourth Proportional to 640.86, 961.33 and 275.65

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Solution

The fourth proportional to 640.86, 961.33 and 275.65 is: 413.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.86 : 961.33 = 275.65 : x
  2. Step 2: Convert to fraction form
    640.86/961.33 = 275.65/x
  3. Step 3: Cross multiply
    640.86x = 961.33 × 275.65
  4. Step 4: Simplify right side
    640.86x = 264,990.61
  5. Step 5: Solve for x
    x = 264,990.61/640.86
  6. Step 6: Final answer
    x = 413.49

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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.