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Finding the Fourth Proportional to 728.31, 1,005.11 and 413.45

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Solution

The fourth proportional to 728.31, 1,005.11 and 413.45 is: 570.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    728.31 : 1,005.11 = 413.45 : x
  2. Step 2: Convert to fraction form
    728.31/1,005.11 = 413.45/x
  3. Step 3: Cross multiply
    728.31x = 1,005.11 × 413.45
  4. Step 4: Simplify right side
    728.31x = 415,566.28
  5. Step 5: Solve for x
    x = 415,566.28/728.31
  6. Step 6: Final answer
    x = 570.59

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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.