Finding the Fourth Proportional to 2,081.86, 3,123.24 and 621.13

Step by Step Solution

1. Step 1: Write the proportion equation
   2,081.86 : 3,123.24 = 621.13 : x
2. Step 2: Convert to fraction form
   2,081.86/3,123.24 = 621.13/x
3. Step 3: Cross multiply
   2,081.86x = 3,123.24 × 621.13
4. Step 4: Simplify right side
   2,081.86x = 1,939,938.06
5. Step 5: Solve for x
   x = 1,939,938.06/2,081.86
6. Step 6: Final answer
   x = 931.83