Finding the Fourth Proportional to 2,485.91, 3,422.72 and 2,112.30

Step by Step Solution

1. Step 1: Write the proportion equation
   2,485.91 : 3,422.72 = 2,112.30 : x
2. Step 2: Convert to fraction form
   2,485.91/3,422.72 = 2,112.30/x
3. Step 3: Cross multiply
   2,485.91x = 3,422.72 × 2,112.30
4. Step 4: Simplify right side
   2,485.91x = 7,229,816.74
5. Step 5: Solve for x
   x = 7,229,816.74/2,485.91
6. Step 6: Final answer
   x = 2,908.32