Finding the Fourth Proportional to 1,355.60, 1,868.04 and 1,005.68

Step by Step Solution

1. Step 1: Write the proportion equation
   1,355.60 : 1,868.04 = 1,005.68 : x
2. Step 2: Convert to fraction form
   1,355.60/1,868.04 = 1,005.68/x
3. Step 3: Cross multiply
   1,355.60x = 1,868.04 × 1,005.68
4. Step 4: Simplify right side
   1,355.60x = 1,878,650.47
5. Step 5: Solve for x
   x = 1,878,650.47/1,355.60
6. Step 6: Final answer
   x = 1,385.84