Finding the Fourth Proportional to 2,128.06, 3,186.14 and 1,085.80

Step by Step Solution

1. Step 1: Write the proportion equation
   2,128.06 : 3,186.14 = 1,085.80 : x
2. Step 2: Convert to fraction form
   2,128.06/3,186.14 = 1,085.80/x
3. Step 3: Cross multiply
   2,128.06x = 3,186.14 × 1,085.80
4. Step 4: Simplify right side
   2,128.06x = 3,459,510.81
5. Step 5: Solve for x
   x = 3,459,510.81/2,128.06
6. Step 6: Final answer
   x = 1,625.66