Finding the Fourth Proportional to 2,592.56, 3,887.22 and 860.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,592.56 : 3,887.22 = 860.78 : x
2. Step 2: Convert to fraction form
   2,592.56/3,887.22 = 860.78/x
3. Step 3: Cross multiply
   2,592.56x = 3,887.22 × 860.78
4. Step 4: Simplify right side
   2,592.56x = 3,346,041.23
5. Step 5: Solve for x
   x = 3,346,041.23/2,592.56
6. Step 6: Final answer
   x = 1,290.63