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Finding the Fourth Proportional to 729.12, 1,005.96 and 418.56

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Solution

The fourth proportional to 729.12, 1,005.96 and 418.56 is: 577.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    729.12 : 1,005.96 = 418.56 : x
  2. Step 2: Convert to fraction form
    729.12/1,005.96 = 418.56/x
  3. Step 3: Cross multiply
    729.12x = 1,005.96 × 418.56
  4. Step 4: Simplify right side
    729.12x = 421,054.62
  5. Step 5: Solve for x
    x = 421,054.62/729.12
  6. Step 6: Final answer
    x = 577.48

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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.