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Finding the Fourth Proportional to 121.08, 181.51 and 39.87

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Solution

The fourth proportional to 121.08, 181.51 and 39.87 is: 59.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    121.08 : 181.51 = 39.87 : x
  2. Step 2: Convert to fraction form
    121.08/181.51 = 39.87/x
  3. Step 3: Cross multiply
    121.08x = 181.51 × 39.87
  4. Step 4: Simplify right side
    121.08x = 7,236.28
  5. Step 5: Solve for x
    x = 7,236.28/121.08
  6. Step 6: Final answer
    x = 59.76

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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.