Finding the Fourth Proportional to 1,868.72, 2,578.86 and 1,040.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,868.72 : 2,578.86 = 1,040.72 : x
2. Step 2: Convert to fraction form
   1,868.72/2,578.86 = 1,040.72/x
3. Step 3: Cross multiply
   1,868.72x = 2,578.86 × 1,040.72
4. Step 4: Simplify right side
   1,868.72x = 2,683,871.18
5. Step 5: Solve for x
   x = 2,683,871.18/1,868.72
6. Step 6: Final answer
   x = 1,436.21