Finding the Fourth Proportional to 1,371.80, 1,893.22 and 812.45

Step by Step Solution

1. Step 1: Write the proportion equation
   1,371.80 : 1,893.22 = 812.45 : x
2. Step 2: Convert to fraction form
   1,371.80/1,893.22 = 812.45/x
3. Step 3: Cross multiply
   1,371.80x = 1,893.22 × 812.45
4. Step 4: Simplify right side
   1,371.80x = 1,538,146.59
5. Step 5: Solve for x
   x = 1,538,146.59/1,371.80
6. Step 6: Final answer
   x = 1,121.26