Finding the Fourth Proportional to 7,145.48, 9,859.83 and 4,120.72

Step by Step Solution

1. Step 1: Write the proportion equation
   7,145.48 : 9,859.83 = 4,120.72 : x
2. Step 2: Convert to fraction form
   7,145.48/9,859.83 = 4,120.72/x
3. Step 3: Cross multiply
   7,145.48x = 9,859.83 × 4,120.72
4. Step 4: Simplify right side
   7,145.48x = 40,629,574.03
5. Step 5: Solve for x
   x = 40,629,574.03/7,145.48
6. Step 6: Final answer
   x = 5,686.05