Finding the Fourth Proportional to 2,611.54, 3,916.34 and 879.76

Step by Step Solution

1. Step 1: Write the proportion equation
   2,611.54 : 3,916.34 = 879.76 : x
2. Step 2: Convert to fraction form
   2,611.54/3,916.34 = 879.76/x
3. Step 3: Cross multiply
   2,611.54x = 3,916.34 × 879.76
4. Step 4: Simplify right side
   2,611.54x = 3,445,439.28
5. Step 5: Solve for x
   x = 3,445,439.28/2,611.54
6. Step 6: Final answer
   x = 1,319.31