Finding the Fourth Proportional to 1,921.92, 2,880.72 and 766.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,921.92 : 2,880.72 = 766.56 : x
2. Step 2: Convert to fraction form
   1,921.92/2,880.72 = 766.56/x
3. Step 3: Cross multiply
   1,921.92x = 2,880.72 × 766.56
4. Step 4: Simplify right side
   1,921.92x = 2,208,244.72
5. Step 5: Solve for x
   x = 2,208,244.72/1,921.92
6. Step 6: Final answer
   x = 1,148.98