Finding the Fourth Proportional to 1,638.52, 2,448.20 and 1,581.11

Step by Step Solution

1. Step 1: Write the proportion equation
   1,638.52 : 2,448.20 = 1,581.11 : x
2. Step 2: Convert to fraction form
   1,638.52/2,448.20 = 1,581.11/x
3. Step 3: Cross multiply
   1,638.52x = 2,448.20 × 1,581.11
4. Step 4: Simplify right side
   1,638.52x = 3,870,873.50
5. Step 5: Solve for x
   x = 3,870,873.50/1,638.52
6. Step 6: Final answer
   x = 2,362.42