Finding the Fourth Proportional to 1,376.88, 1,899.59 and 905.03

Step by Step Solution

1. Step 1: Write the proportion equation
   1,376.88 : 1,899.59 = 905.03 : x
2. Step 2: Convert to fraction form
   1,376.88/1,899.59 = 905.03/x
3. Step 3: Cross multiply
   1,376.88x = 1,899.59 × 905.03
4. Step 4: Simplify right side
   1,376.88x = 1,719,185.94
5. Step 5: Solve for x
   x = 1,719,185.94/1,376.88
6. Step 6: Final answer
   x = 1,248.61