Finding the Fourth Proportional to 2,153.75, 2,972.06 and 1,222.55

Step by Step Solution

1. Step 1: Write the proportion equation
   2,153.75 : 2,972.06 = 1,222.55 : x
2. Step 2: Convert to fraction form
   2,153.75/2,972.06 = 1,222.55/x
3. Step 3: Cross multiply
   2,153.75x = 2,972.06 × 1,222.55
4. Step 4: Simplify right side
   2,153.75x = 3,633,480.15
5. Step 5: Solve for x
   x = 3,633,480.15/2,153.75
6. Step 6: Final answer
   x = 1,687.05