Finding the Fourth Proportional to 8,085.40, 12,128.20 and 2,538.52

Step by Step Solution

1. Step 1: Write the proportion equation
   8,085.40 : 12,128.20 = 2,538.52 : x
2. Step 2: Convert to fraction form
   8,085.40/12,128.20 = 2,538.52/x
3. Step 3: Cross multiply
   8,085.40x = 12,128.20 × 2,538.52
4. Step 4: Simplify right side
   8,085.40x = 30,787,678.26
5. Step 5: Solve for x
   x = 30,787,678.26/8,085.40
6. Step 6: Final answer
   x = 3,807.81