Finding the Fourth Proportional to 1,651.92, 2,478.72 and 678.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,651.92 : 2,478.72 = 678.72 : x
2. Step 2: Convert to fraction form
   1,651.92/2,478.72 = 678.72/x
3. Step 3: Cross multiply
   1,651.92x = 2,478.72 × 678.72
4. Step 4: Simplify right side
   1,651.92x = 1,682,356.84
5. Step 5: Solve for x
   x = 1,682,356.84/1,651.92
6. Step 6: Final answer
   x = 1,018.43