Finding the Fourth Proportional to 1,940.31, 2,910.50 and 1,080.09

Step by Step Solution

1. Step 1: Write the proportion equation
   1,940.31 : 2,910.50 = 1,080.09 : x
2. Step 2: Convert to fraction form
   1,940.31/2,910.50 = 1,080.09/x
3. Step 3: Cross multiply
   1,940.31x = 2,910.50 × 1,080.09
4. Step 4: Simplify right side
   1,940.31x = 3,143,596.54
5. Step 5: Solve for x
   x = 3,143,596.54/1,940.31
6. Step 6: Final answer
   x = 1,620.15