Finding the Fourth Proportional to 3,665.21, 5,057.87 and 2,071.91

Step by Step Solution

1. Step 1: Write the proportion equation
   3,665.21 : 5,057.87 = 2,071.91 : x
2. Step 2: Convert to fraction form
   3,665.21/5,057.87 = 2,071.91/x
3. Step 3: Cross multiply
   3,665.21x = 5,057.87 × 2,071.91
4. Step 4: Simplify right side
   3,665.21x = 10,479,453.72
5. Step 5: Solve for x
   x = 10,479,453.72/3,665.21
6. Step 6: Final answer
   x = 2,859.17