Finding the Fourth Proportional to 1,380.30, 1,902.58 and 1,081.03

Step by Step Solution

1. Step 1: Write the proportion equation
   1,380.30 : 1,902.58 = 1,081.03 : x
2. Step 2: Convert to fraction form
   1,380.30/1,902.58 = 1,081.03/x
3. Step 3: Cross multiply
   1,380.30x = 1,902.58 × 1,081.03
4. Step 4: Simplify right side
   1,380.30x = 2,056,746.06
5. Step 5: Solve for x
   x = 2,056,746.06/1,380.30
6. Step 6: Final answer
   x = 1,490.07