Finding the Fourth Proportional to 1,371.80, 1,893.12 and 840.62

Step by Step Solution

1. Step 1: Write the proportion equation
   1,371.80 : 1,893.12 = 840.62 : x
2. Step 2: Convert to fraction form
   1,371.80/1,893.12 = 840.62/x
3. Step 3: Cross multiply
   1,371.80x = 1,893.12 × 840.62
4. Step 4: Simplify right side
   1,371.80x = 1,591,394.53
5. Step 5: Solve for x
   x = 1,591,394.53/1,371.80
6. Step 6: Final answer
   x = 1,160.08