Finding the Fourth Proportional to 1,081.89, 1,620.41 and 774.09

Step by Step Solution

1. Step 1: Write the proportion equation
   1,081.89 : 1,620.41 = 774.09 : x
2. Step 2: Convert to fraction form
   1,081.89/1,620.41 = 774.09/x
3. Step 3: Cross multiply
   1,081.89x = 1,620.41 × 774.09
4. Step 4: Simplify right side
   1,081.89x = 1,254,339.31
5. Step 5: Solve for x
   x = 1,254,339.31/1,081.89
6. Step 6: Final answer
   x = 1,159.40