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Finding the Fourth Proportional to 721.08, 994.43 and 485.22

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Solution

The fourth proportional to 721.08, 994.43 and 485.22 is: 669.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.08 : 994.43 = 485.22 : x
  2. Step 2: Convert to fraction form
    721.08/994.43 = 485.22/x
  3. Step 3: Cross multiply
    721.08x = 994.43 × 485.22
  4. Step 4: Simplify right side
    721.08x = 482,514.90
  5. Step 5: Solve for x
    x = 482,514.90/721.08
  6. Step 6: Final answer
    x = 669.16

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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.