Finding the Fourth Proportional to 1,381.17, 1,903.79 and 1,081.91

Step by Step Solution

1. Step 1: Write the proportion equation
   1,381.17 : 1,903.79 = 1,081.91 : x
2. Step 2: Convert to fraction form
   1,381.17/1,903.79 = 1,081.91/x
3. Step 3: Cross multiply
   1,381.17x = 1,903.79 × 1,081.91
4. Step 4: Simplify right side
   1,381.17x = 2,059,714.51
5. Step 5: Solve for x
   x = 2,059,714.51/1,381.17
6. Step 6: Final answer
   x = 1,491.28