Finding the Fourth Proportional to 2,705.58, 4,057.78 and 856.84

Step by Step Solution

1. Step 1: Write the proportion equation
   2,705.58 : 4,057.78 = 856.84 : x
2. Step 2: Convert to fraction form
   2,705.58/4,057.78 = 856.84/x
3. Step 3: Cross multiply
   2,705.58x = 4,057.78 × 856.84
4. Step 4: Simplify right side
   2,705.58x = 3,476,868.22
5. Step 5: Solve for x
   x = 3,476,868.22/2,705.58
6. Step 6: Final answer
   x = 1,285.07