Finding the Fourth Proportional to 1,086.63, 1,629.96 and 718.79

Step by Step Solution

1. Step 1: Write the proportion equation
   1,086.63 : 1,629.96 = 718.79 : x
2. Step 2: Convert to fraction form
   1,086.63/1,629.96 = 718.79/x
3. Step 3: Cross multiply
   1,086.63x = 1,629.96 × 718.79
4. Step 4: Simplify right side
   1,086.63x = 1,171,591.28
5. Step 5: Solve for x
   x = 1,171,591.28/1,086.63
6. Step 6: Final answer
   x = 1,078.19