Finding the Fourth Proportional to 1,357.63, 1,871.71 and 1,078.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,357.63 : 1,871.71 = 1,078.78 : x
2. Step 2: Convert to fraction form
   1,357.63/1,871.71 = 1,078.78/x
3. Step 3: Cross multiply
   1,357.63x = 1,871.71 × 1,078.78
4. Step 4: Simplify right side
   1,357.63x = 2,019,163.31
5. Step 5: Solve for x
   x = 2,019,163.31/1,357.63
6. Step 6: Final answer
   x = 1,487.27