Finding the Fourth Proportional to 1,368.89, 1,889.41 and 779.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,368.89 : 1,889.41 = 779.78 : x
2. Step 2: Convert to fraction form
   1,368.89/1,889.41 = 779.78/x
3. Step 3: Cross multiply
   1,368.89x = 1,889.41 × 779.78
4. Step 4: Simplify right side
   1,368.89x = 1,473,312.73
5. Step 5: Solve for x
   x = 1,473,312.73/1,368.89
6. Step 6: Final answer
   x = 1,076.28