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Finding the Fourth Proportional to 121.60, 181.60 and 115.12

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Solution

The fourth proportional to 121.60, 181.60 and 115.12 is: 171.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    121.60 : 181.60 = 115.12 : x
  2. Step 2: Convert to fraction form
    121.60/181.60 = 115.12/x
  3. Step 3: Cross multiply
    121.60x = 181.60 × 115.12
  4. Step 4: Simplify right side
    121.60x = 20,905.79
  5. Step 5: Solve for x
    x = 20,905.79/121.60
  6. Step 6: Final answer
    x = 171.92

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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.