Finding the Fourth Proportional to 1,873.55, 2,811.72 and 1,387.91

Step by Step Solution

1. Step 1: Write the proportion equation
   1,873.55 : 2,811.72 = 1,387.91 : x
2. Step 2: Convert to fraction form
   1,873.55/2,811.72 = 1,387.91/x
3. Step 3: Cross multiply
   1,873.55x = 2,811.72 × 1,387.91
4. Step 4: Simplify right side
   1,873.55x = 3,902,414.31
5. Step 5: Solve for x
   x = 3,902,414.31/1,873.55
6. Step 6: Final answer
   x = 2,082.90