Finding the Fourth Proportional to 3,870.15, 5,807.36 and 2,115.09

Step by Step Solution

1. Step 1: Write the proportion equation
   3,870.15 : 5,807.36 = 2,115.09 : x
2. Step 2: Convert to fraction form
   3,870.15/5,807.36 = 2,115.09/x
3. Step 3: Cross multiply
   3,870.15x = 5,807.36 × 2,115.09
4. Step 4: Simplify right side
   3,870.15x = 12,283,078.49
5. Step 5: Solve for x
   x = 12,283,078.49/3,870.15
6. Step 6: Final answer
   x = 3,173.80