Finding the Fourth Proportional to 1,913.50, 2,640.63 and 1,085.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,913.50 : 2,640.63 = 1,085.50 : x
2. Step 2: Convert to fraction form
   1,913.50/2,640.63 = 1,085.50/x
3. Step 3: Cross multiply
   1,913.50x = 2,640.63 × 1,085.50
4. Step 4: Simplify right side
   1,913.50x = 2,866,403.87
5. Step 5: Solve for x
   x = 2,866,403.87/1,913.50
6. Step 6: Final answer
   x = 1,497.99