Finding the Fourth Proportional to 1,920.65, 2,650.57 and 1,081.35

Step by Step Solution

1. Step 1: Write the proportion equation
   1,920.65 : 2,650.57 = 1,081.35 : x
2. Step 2: Convert to fraction form
   1,920.65/2,650.57 = 1,081.35/x
3. Step 3: Cross multiply
   1,920.65x = 2,650.57 × 1,081.35
4. Step 4: Simplify right side
   1,920.65x = 2,866,191.17
5. Step 5: Solve for x
   x = 2,866,191.17/1,920.65
6. Step 6: Final answer
   x = 1,492.31