Finding the Fourth Proportional to 1,651.31, 2,278.81 and 905.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,651.31 : 2,278.81 = 905.30 : x
2. Step 2: Convert to fraction form
   1,651.31/2,278.81 = 905.30/x
3. Step 3: Cross multiply
   1,651.31x = 2,278.81 × 905.30
4. Step 4: Simplify right side
   1,651.31x = 2,062,990.77
5. Step 5: Solve for x
   x = 2,062,990.77/1,651.31
6. Step 6: Final answer
   x = 1,249.31