Finding the Fourth Proportional to 1,289.10, 1,935.72 and 1,085.34

Step by Step Solution

1. Step 1: Write the proportion equation
   1,289.10 : 1,935.72 = 1,085.34 : x
2. Step 2: Convert to fraction form
   1,289.10/1,935.72 = 1,085.34/x
3. Step 3: Cross multiply
   1,289.10x = 1,935.72 × 1,085.34
4. Step 4: Simplify right side
   1,289.10x = 2,100,914.34
5. Step 5: Solve for x
   x = 2,100,914.34/1,289.10
6. Step 6: Final answer
   x = 1,629.75