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Finding the Fourth Proportional to 680.28, 939.11 and 459.15

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Solution

The fourth proportional to 680.28, 939.11 and 459.15 is: 633.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.28 : 939.11 = 459.15 : x
  2. Step 2: Convert to fraction form
    680.28/939.11 = 459.15/x
  3. Step 3: Cross multiply
    680.28x = 939.11 × 459.15
  4. Step 4: Simplify right side
    680.28x = 431,190.06
  5. Step 5: Solve for x
    x = 431,190.06/680.28
  6. Step 6: Final answer
    x = 633.84

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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.