Finding the Fourth Proportional to 2,105.10, 3,156.93 and 699.21

Step by Step Solution

1. Step 1: Write the proportion equation
   2,105.10 : 3,156.93 = 699.21 : x
2. Step 2: Convert to fraction form
   2,105.10/3,156.93 = 699.21/x
3. Step 3: Cross multiply
   2,105.10x = 3,156.93 × 699.21
4. Step 4: Simplify right side
   2,105.10x = 2,207,357.03
5. Step 5: Solve for x
   x = 2,207,357.03/2,105.10
6. Step 6: Final answer
   x = 1,048.58