Finding the Fourth Proportional to 2,639.86, 3,957.05 and 995.69

Step by Step Solution

1. Step 1: Write the proportion equation
   2,639.86 : 3,957.05 = 995.69 : x
2. Step 2: Convert to fraction form
   2,639.86/3,957.05 = 995.69/x
3. Step 3: Cross multiply
   2,639.86x = 3,957.05 × 995.69
4. Step 4: Simplify right side
   2,639.86x = 3,940,007.50
5. Step 5: Solve for x
   x = 3,940,007.50/2,639.86
6. Step 6: Final answer
   x = 1,492.51