Finding the Fourth Proportional to 2,155.78, 2,974.98 and 1,224.28

Step by Step Solution

1. Step 1: Write the proportion equation
   2,155.78 : 2,974.98 = 1,224.28 : x
2. Step 2: Convert to fraction form
   2,155.78/2,974.98 = 1,224.28/x
3. Step 3: Cross multiply
   2,155.78x = 2,974.98 × 1,224.28
4. Step 4: Simplify right side
   2,155.78x = 3,642,208.51
5. Step 5: Solve for x
   x = 3,642,208.51/2,155.78
6. Step 6: Final answer
   x = 1,689.51