Finding the Fourth Proportional to 1,371.75, 1,891.34 and 1,039.60

Step by Step Solution

1. Step 1: Write the proportion equation
   1,371.75 : 1,891.34 = 1,039.60 : x
2. Step 2: Convert to fraction form
   1,371.75/1,891.34 = 1,039.60/x
3. Step 3: Cross multiply
   1,371.75x = 1,891.34 × 1,039.60
4. Step 4: Simplify right side
   1,371.75x = 1,966,227.61
5. Step 5: Solve for x
   x = 1,966,227.61/1,371.75
6. Step 6: Final answer
   x = 1,433.37