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Finding the Fourth Proportional to 728.57, 998.20 and 719.47

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Solution

The fourth proportional to 728.57, 998.20 and 719.47 is: 985.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    728.57 : 998.20 = 719.47 : x
  2. Step 2: Convert to fraction form
    728.57/998.20 = 719.47/x
  3. Step 3: Cross multiply
    728.57x = 998.20 × 719.47
  4. Step 4: Simplify right side
    728.57x = 718,169.96
  5. Step 5: Solve for x
    x = 718,169.96/728.57
  6. Step 6: Final answer
    x = 985.73

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.