Finding the Fourth Proportional to 2,615.56, 3,921.84 and 1,056.31

Step by Step Solution

1. Step 1: Write the proportion equation
   2,615.56 : 3,921.84 = 1,056.31 : x
2. Step 2: Convert to fraction form
   2,615.56/3,921.84 = 1,056.31/x
3. Step 3: Cross multiply
   2,615.56x = 3,921.84 × 1,056.31
4. Step 4: Simplify right side
   2,615.56x = 4,142,669.01
5. Step 5: Solve for x
   x = 4,142,669.01/2,615.56
6. Step 6: Final answer
   x = 1,583.86