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Finding the Fourth Proportional to 121.72, 181.51 and 120.62

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Solution

The fourth proportional to 121.72, 181.51 and 120.62 is: 179.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    121.72 : 181.51 = 120.62 : x
  2. Step 2: Convert to fraction form
    121.72/181.51 = 120.62/x
  3. Step 3: Cross multiply
    121.72x = 181.51 × 120.62
  4. Step 4: Simplify right side
    121.72x = 21,892.23
  5. Step 5: Solve for x
    x = 21,892.23/121.72
  6. Step 6: Final answer
    x = 179.86

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.