Finding the Fourth Proportional to 2,081.18, 2,868.72 and 1,638.38

Step by Step Solution

1. Step 1: Write the proportion equation
   2,081.18 : 2,868.72 = 1,638.38 : x
2. Step 2: Convert to fraction form
   2,081.18/2,868.72 = 1,638.38/x
3. Step 3: Cross multiply
   2,081.18x = 2,868.72 × 1,638.38
4. Step 4: Simplify right side
   2,081.18x = 4,700,053.47
5. Step 5: Solve for x
   x = 4,700,053.47/2,081.18
6. Step 6: Final answer
   x = 2,258.36