Finding the Fourth Proportional to 2,807.96, 4,211.07 and 860.10

Step by Step Solution

1. Step 1: Write the proportion equation
   2,807.96 : 4,211.07 = 860.10 : x
2. Step 2: Convert to fraction form
   2,807.96/4,211.07 = 860.10/x
3. Step 3: Cross multiply
   2,807.96x = 4,211.07 × 860.10
4. Step 4: Simplify right side
   2,807.96x = 3,621,941.31
5. Step 5: Solve for x
   x = 3,621,941.31/2,807.96
6. Step 6: Final answer
   x = 1,289.89