Finding the Fourth Proportional to 1,815.12, 2,720.52 and 1,380.96

Step by Step Solution

1. Step 1: Write the proportion equation
   1,815.12 : 2,720.52 = 1,380.96 : x
2. Step 2: Convert to fraction form
   1,815.12/2,720.52 = 1,380.96/x
3. Step 3: Cross multiply
   1,815.12x = 2,720.52 × 1,380.96
4. Step 4: Simplify right side
   1,815.12x = 3,756,929.30
5. Step 5: Solve for x
   x = 3,756,929.30/1,815.12
6. Step 6: Final answer
   x = 2,069.80