Finding the Fourth Proportional to 2,538.56, 3,807.90 and 807.20

Step by Step Solution

1. Step 1: Write the proportion equation
   2,538.56 : 3,807.90 = 807.20 : x
2. Step 2: Convert to fraction form
   2,538.56/3,807.90 = 807.20/x
3. Step 3: Cross multiply
   2,538.56x = 3,807.90 × 807.20
4. Step 4: Simplify right side
   2,538.56x = 3,073,736.88
5. Step 5: Solve for x
   x = 3,073,736.88/2,538.56
6. Step 6: Final answer
   x = 1,210.82