Finding the Fourth Proportional to 1,371.51, 1,892.61 and 811.98

Step by Step Solution

1. Step 1: Write the proportion equation
   1,371.51 : 1,892.61 = 811.98 : x
2. Step 2: Convert to fraction form
   1,371.51/1,892.61 = 811.98/x
3. Step 3: Cross multiply
   1,371.51x = 1,892.61 × 811.98
4. Step 4: Simplify right side
   1,371.51x = 1,536,761.47
5. Step 5: Solve for x
   x = 1,536,761.47/1,371.51
6. Step 6: Final answer
   x = 1,120.49