Finding the Fourth Proportional to 2,659.92, 3,990.32 and 905.03

Step by Step Solution

1. Step 1: Write the proportion equation
   2,659.92 : 3,990.32 = 905.03 : x
2. Step 2: Convert to fraction form
   2,659.92/3,990.32 = 905.03/x
3. Step 3: Cross multiply
   2,659.92x = 3,990.32 × 905.03
4. Step 4: Simplify right side
   2,659.92x = 3,611,334.83
5. Step 5: Solve for x
   x = 3,611,334.83/2,659.92
6. Step 6: Final answer
   x = 1,357.69