Finding the Fourth Proportional to 2,085.55, 3,131.90 and 1,851.81

Step by Step Solution

1. Step 1: Write the proportion equation
   2,085.55 : 3,131.90 = 1,851.81 : x
2. Step 2: Convert to fraction form
   2,085.55/3,131.90 = 1,851.81/x
3. Step 3: Cross multiply
   2,085.55x = 3,131.90 × 1,851.81
4. Step 4: Simplify right side
   2,085.55x = 5,799,674.48
5. Step 5: Solve for x
   x = 5,799,674.48/2,085.55
6. Step 6: Final answer
   x = 2,780.89