Finding the Fourth Proportional to 1,366.53, 1,886.12 and 868.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,366.53 : 1,886.12 = 868.78 : x
2. Step 2: Convert to fraction form
   1,366.53/1,886.12 = 868.78/x
3. Step 3: Cross multiply
   1,366.53x = 1,886.12 × 868.78
4. Step 4: Simplify right side
   1,366.53x = 1,638,623.33
5. Step 5: Solve for x
   x = 1,638,623.33/1,366.53
6. Step 6: Final answer
   x = 1,199.11