Finding the Fourth Proportional to 1,376.89, 1,899.92 and 809.49

Step by Step Solution

1. Step 1: Write the proportion equation
   1,376.89 : 1,899.92 = 809.49 : x
2. Step 2: Convert to fraction form
   1,376.89/1,899.92 = 809.49/x
3. Step 3: Cross multiply
   1,376.89x = 1,899.92 × 809.49
4. Step 4: Simplify right side
   1,376.89x = 1,537,966.24
5. Step 5: Solve for x
   x = 1,537,966.24/1,376.89
6. Step 6: Final answer
   x = 1,116.99