Finding the Fourth Proportional to 81,082.42, 121,679 and 28,491.91

Step by Step Solution

1. Step 1: Write the proportion equation
   81,082.42 : 121,679 = 28,491.91 : x
2. Step 2: Convert to fraction form
   81,082.42/121,679 = 28,491.91/x
3. Step 3: Cross multiply
   81,082.42x = 121,679 × 28,491.91
4. Step 4: Simplify right side
   81,082.42x = 3,466,867,116.89
5. Step 5: Solve for x
   x = 3,466,867,116.89/81,082.42
6. Step 6: Final answer
   x = 42,757.32