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Finding the Fourth Proportional to 493.91, 740.87 and 128.71

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Solution

The fourth proportional to 493.91, 740.87 and 128.71 is: 193.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    493.91 : 740.87 = 128.71 : x
  2. Step 2: Convert to fraction form
    493.91/740.87 = 128.71/x
  3. Step 3: Cross multiply
    493.91x = 740.87 × 128.71
  4. Step 4: Simplify right side
    493.91x = 95,357.38
  5. Step 5: Solve for x
    x = 95,357.38/493.91
  6. Step 6: Final answer
    x = 193.07

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.