Finding the Fourth Proportional to 2,094.78, 3,139.50 and 860.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,094.78 : 3,139.50 = 860.78 : x
2. Step 2: Convert to fraction form
   2,094.78/3,139.50 = 860.78/x
3. Step 3: Cross multiply
   2,094.78x = 3,139.50 × 860.78
4. Step 4: Simplify right side
   2,094.78x = 2,702,418.81
5. Step 5: Solve for x
   x = 2,702,418.81/2,094.78
6. Step 6: Final answer
   x = 1,290.07