Finding the Fourth Proportional to 2,185.50, 3,278.73 and 817.50

Step by Step Solution

1. Step 1: Write the proportion equation
   2,185.50 : 3,278.73 = 817.50 : x
2. Step 2: Convert to fraction form
   2,185.50/3,278.73 = 817.50/x
3. Step 3: Cross multiply
   2,185.50x = 3,278.73 × 817.50
4. Step 4: Simplify right side
   2,185.50x = 2,680,361.78
5. Step 5: Solve for x
   x = 2,680,361.78/2,185.50
6. Step 6: Final answer
   x = 1,226.43