Finding the Fourth Proportional to 2,081.20, 3,123.36 and 985.88

Step by Step Solution

1. Step 1: Write the proportion equation
   2,081.20 : 3,123.36 = 985.88 : x
2. Step 2: Convert to fraction form
   2,081.20/3,123.36 = 985.88/x
3. Step 3: Cross multiply
   2,081.20x = 3,123.36 × 985.88
4. Step 4: Simplify right side
   2,081.20x = 3,079,258.16
5. Step 5: Solve for x
   x = 3,079,258.16/2,081.20
6. Step 6: Final answer
   x = 1,479.56