Finding the Fourth Proportional to 1,176.10, 1,766.42 and 1,128.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,176.10 : 1,766.42 = 1,128.78 : x
2. Step 2: Convert to fraction form
   1,176.10/1,766.42 = 1,128.78/x
3. Step 3: Cross multiply
   1,176.10x = 1,766.42 × 1,128.78
4. Step 4: Simplify right side
   1,176.10x = 1,993,899.57
5. Step 5: Solve for x
   x = 1,993,899.57/1,176.10
6. Step 6: Final answer
   x = 1,695.35