Finding the Fourth Proportional to 1,392.57, 2,097.12 and 1,212.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,392.57 : 2,097.12 = 1,212.15 : x
2. Step 2: Convert to fraction form
   1,392.57/2,097.12 = 1,212.15/x
3. Step 3: Cross multiply
   1,392.57x = 2,097.12 × 1,212.15
4. Step 4: Simplify right side
   1,392.57x = 2,542,024.01
5. Step 5: Solve for x
   x = 2,542,024.01/1,392.57
6. Step 6: Final answer
   x = 1,825.42