Finding the Fourth Proportional to 2,105.16, 2,905.20 and 1,161.06

Step by Step Solution

1. Step 1: Write the proportion equation
   2,105.16 : 2,905.20 = 1,161.06 : x
2. Step 2: Convert to fraction form
   2,105.16/2,905.20 = 1,161.06/x
3. Step 3: Cross multiply
   2,105.16x = 2,905.20 × 1,161.06
4. Step 4: Simplify right side
   2,105.16x = 3,373,111.51
5. Step 5: Solve for x
   x = 3,373,111.51/2,105.16
6. Step 6: Final answer
   x = 1,602.31