Finding the Fourth Proportional to 1,222.29, 1,687.55 and 1,091.07

Step by Step Solution

1. Step 1: Write the proportion equation
   1,222.29 : 1,687.55 = 1,091.07 : x
2. Step 2: Convert to fraction form
   1,222.29/1,687.55 = 1,091.07/x
3. Step 3: Cross multiply
   1,222.29x = 1,687.55 × 1,091.07
4. Step 4: Simplify right side
   1,222.29x = 1,841,229.72
5. Step 5: Solve for x
   x = 1,841,229.72/1,222.29
6. Step 6: Final answer
   x = 1,506.38