Finding the Fourth Proportional to 1,078.72, 1,614.74 and 871.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,078.72 : 1,614.74 = 871.56 : x
2. Step 2: Convert to fraction form
   1,078.72/1,614.74 = 871.56/x
3. Step 3: Cross multiply
   1,078.72x = 1,614.74 × 871.56
4. Step 4: Simplify right side
   1,078.72x = 1,407,338.44
5. Step 5: Solve for x
   x = 1,407,338.44/1,078.72
6. Step 6: Final answer
   x = 1,304.64