Finding the Fourth Proportional to 2,111.77, 3,168.09 and 724.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,111.77 : 3,168.09 = 724.78 : x
2. Step 2: Convert to fraction form
   2,111.77/3,168.09 = 724.78/x
3. Step 3: Cross multiply
   2,111.77x = 3,168.09 × 724.78
4. Step 4: Simplify right side
   2,111.77x = 2,296,148.81
5. Step 5: Solve for x
   x = 2,296,148.81/2,111.77
6. Step 6: Final answer
   x = 1,087.31