Finding the Fourth Proportional to 2,155.31, 2,974.08 and 1,211.12

Step by Step Solution

1. Step 1: Write the proportion equation
   2,155.31 : 2,974.08 = 1,211.12 : x
2. Step 2: Convert to fraction form
   2,155.31/2,974.08 = 1,211.12/x
3. Step 3: Cross multiply
   2,155.31x = 2,974.08 × 1,211.12
4. Step 4: Simplify right side
   2,155.31x = 3,601,967.77
5. Step 5: Solve for x
   x = 3,601,967.77/2,155.31
6. Step 6: Final answer
   x = 1,671.21