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Finding the Fourth Proportional to 121.26, 180.72 and 120.30

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Solution

The fourth proportional to 121.26, 180.72 and 120.30 is: 179.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    121.26 : 180.72 = 120.30 : x
  2. Step 2: Convert to fraction form
    121.26/180.72 = 120.30/x
  3. Step 3: Cross multiply
    121.26x = 180.72 × 120.30
  4. Step 4: Simplify right side
    121.26x = 21,740.62
  5. Step 5: Solve for x
    x = 21,740.62/121.26
  6. Step 6: Final answer
    x = 179.29

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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.