Finding the Fourth Proportional to 2,081.42, 3,123.67 and 985.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,081.42 : 3,123.67 = 985.78 : x
2. Step 2: Convert to fraction form
   2,081.42/3,123.67 = 985.78/x
3. Step 3: Cross multiply
   2,081.42x = 3,123.67 × 985.78
4. Step 4: Simplify right side
   2,081.42x = 3,079,246.48
5. Step 5: Solve for x
   x = 3,079,246.48/2,081.42
6. Step 6: Final answer
   x = 1,479.40