Finding the Fourth Proportional to 1,359.18, 1,876.41 and 939.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,359.18 : 1,876.41 = 939.78 : x
2. Step 2: Convert to fraction form
   1,359.18/1,876.41 = 939.78/x
3. Step 3: Cross multiply
   1,359.18x = 1,876.41 × 939.78
4. Step 4: Simplify right side
   1,359.18x = 1,763,412.59
5. Step 5: Solve for x
   x = 1,763,412.59/1,359.18
6. Step 6: Final answer
   x = 1,297.41