Finding the Fourth Proportional to 3,700.81, 5,107.89 and 2,129.77

Step by Step Solution

1. Step 1: Write the proportion equation
   3,700.81 : 5,107.89 = 2,129.77 : x
2. Step 2: Convert to fraction form
   3,700.81/5,107.89 = 2,129.77/x
3. Step 3: Cross multiply
   3,700.81x = 5,107.89 × 2,129.77
4. Step 4: Simplify right side
   3,700.81x = 10,878,630.89
5. Step 5: Solve for x
   x = 10,878,630.89/3,700.81
6. Step 6: Final answer
   x = 2,939.53