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Finding the Fourth Proportional to 181.07, 249.81 and 128.71

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Solution

The fourth proportional to 181.07, 249.81 and 128.71 is: 177.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    181.07 : 249.81 = 128.71 : x
  2. Step 2: Convert to fraction form
    181.07/249.81 = 128.71/x
  3. Step 3: Cross multiply
    181.07x = 249.81 × 128.71
  4. Step 4: Simplify right side
    181.07x = 32,153.05
  5. Step 5: Solve for x
    x = 32,153.05/181.07
  6. Step 6: Final answer
    x = 177.57

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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.