Finding the Fourth Proportional to 1,080.90, 1,622.52 and 864.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,080.90 : 1,622.52 = 864.72 : x
2. Step 2: Convert to fraction form
   1,080.90/1,622.52 = 864.72/x
3. Step 3: Cross multiply
   1,080.90x = 1,622.52 × 864.72
4. Step 4: Simplify right side
   1,080.90x = 1,403,025.49
5. Step 5: Solve for x
   x = 1,403,025.49/1,080.90
6. Step 6: Final answer
   x = 1,298.02