Finding the Fourth Proportional to 2,611.83, 3,917.10 and 856.38

Step by Step Solution

1. Step 1: Write the proportion equation
   2,611.83 : 3,917.10 = 856.38 : x
2. Step 2: Convert to fraction form
   2,611.83/3,917.10 = 856.38/x
3. Step 3: Cross multiply
   2,611.83x = 3,917.10 × 856.38
4. Step 4: Simplify right side
   2,611.83x = 3,354,526.10
5. Step 5: Solve for x
   x = 3,354,526.10/2,611.83
6. Step 6: Final answer
   x = 1,284.36