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Finding the Fourth Proportional to 721.39, 994.84 and 485.08

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Solution

The fourth proportional to 721.39, 994.84 and 485.08 is: 668.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.39 : 994.84 = 485.08 : x
  2. Step 2: Convert to fraction form
    721.39/994.84 = 485.08/x
  3. Step 3: Cross multiply
    721.39x = 994.84 × 485.08
  4. Step 4: Simplify right side
    721.39x = 482,576.99
  5. Step 5: Solve for x
    x = 482,576.99/721.39
  6. Step 6: Final answer
    x = 668.95

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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.