Finding the Fourth Proportional to 2,155.28, 2,974.10 and 1,211.07

Step by Step Solution

1. Step 1: Write the proportion equation
   2,155.28 : 2,974.10 = 1,211.07 : x
2. Step 2: Convert to fraction form
   2,155.28/2,974.10 = 1,211.07/x
3. Step 3: Cross multiply
   2,155.28x = 2,974.10 × 1,211.07
4. Step 4: Simplify right side
   2,155.28x = 3,601,837.23
5. Step 5: Solve for x
   x = 3,601,837.23/2,155.28
6. Step 6: Final answer
   x = 1,671.17