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Finding the Fourth Proportional to 172.23, 258 and 80.81

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Solution

The fourth proportional to 172.23, 258 and 80.81 is: 121.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    172.23 : 258 = 80.81 : x
  2. Step 2: Convert to fraction form
    172.23/258 = 80.81/x
  3. Step 3: Cross multiply
    172.23x = 258 × 80.81
  4. Step 4: Simplify right side
    172.23x = 20,847.69
  5. Step 5: Solve for x
    x = 20,847.69/172.23
  6. Step 6: Final answer
    x = 121.05

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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.