Finding the Fourth Proportional to 2,611.34, 3,916.28 and 855.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,611.34 : 3,916.28 = 855.72 : x
2. Step 2: Convert to fraction form
   2,611.34/3,916.28 = 855.72/x
3. Step 3: Cross multiply
   2,611.34x = 3,916.28 × 855.72
4. Step 4: Simplify right side
   2,611.34x = 3,351,234.84
5. Step 5: Solve for x
   x = 3,351,234.84/2,611.34
6. Step 6: Final answer
   x = 1,283.34