Finding the Fourth Proportional to 2,771.84, 4,155.71 and 921.87

Step by Step Solution

1. Step 1: Write the proportion equation
   2,771.84 : 4,155.71 = 921.87 : x
2. Step 2: Convert to fraction form
   2,771.84/4,155.71 = 921.87/x
3. Step 3: Cross multiply
   2,771.84x = 4,155.71 × 921.87
4. Step 4: Simplify right side
   2,771.84x = 3,831,019.77
5. Step 5: Solve for x
   x = 3,831,019.77/2,771.84
6. Step 6: Final answer
   x = 1,382.12