Finding the Fourth Proportional to 1,393.18, 1,935.49 and 1,380.49

Step by Step Solution

1. Step 1: Write the proportion equation
   1,393.18 : 1,935.49 = 1,380.49 : x
2. Step 2: Convert to fraction form
   1,393.18/1,935.49 = 1,380.49/x
3. Step 3: Cross multiply
   1,393.18x = 1,935.49 × 1,380.49
4. Step 4: Simplify right side
   1,393.18x = 2,671,924.59
5. Step 5: Solve for x
   x = 2,671,924.59/1,393.18
6. Step 6: Final answer
   x = 1,917.86