Finding the Fourth Proportional to 2,109.12, 3,158.96 and 1,218.56

Step by Step Solution

1. Step 1: Write the proportion equation
   2,109.12 : 3,158.96 = 1,218.56 : x
2. Step 2: Convert to fraction form
   2,109.12/3,158.96 = 1,218.56/x
3. Step 3: Cross multiply
   2,109.12x = 3,158.96 × 1,218.56
4. Step 4: Simplify right side
   2,109.12x = 3,849,382.30
5. Step 5: Solve for x
   x = 3,849,382.30/2,109.12
6. Step 6: Final answer
   x = 1,825.11