Finding the Fourth Proportional to 1,371.05, 1,892.06 and 811.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,371.05 : 1,892.06 = 811.50 : x
2. Step 2: Convert to fraction form
   1,371.05/1,892.06 = 811.50/x
3. Step 3: Cross multiply
   1,371.05x = 1,892.06 × 811.50
4. Step 4: Simplify right side
   1,371.05x = 1,535,408.72
5. Step 5: Solve for x
   x = 1,535,408.72/1,371.05
6. Step 6: Final answer
   x = 1,119.88