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Finding the Fourth Proportional to 728.35, 1,005.15 and 413.61

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Solution

The fourth proportional to 728.35, 1,005.15 and 413.61 is: 570.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    728.35 : 1,005.15 = 413.61 : x
  2. Step 2: Convert to fraction form
    728.35/1,005.15 = 413.61/x
  3. Step 3: Cross multiply
    728.35x = 1,005.15 × 413.61
  4. Step 4: Simplify right side
    728.35x = 415,740.09
  5. Step 5: Solve for x
    x = 415,740.09/728.35
  6. Step 6: Final answer
    x = 570.80

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.