Finding the Fourth Proportional to 3,870.64, 5,340.72 and 2,455.12

Step by Step Solution

1. Step 1: Write the proportion equation
   3,870.64 : 5,340.72 = 2,455.12 : x
2. Step 2: Convert to fraction form
   3,870.64/5,340.72 = 2,455.12/x
3. Step 3: Cross multiply
   3,870.64x = 5,340.72 × 2,455.12
4. Step 4: Simplify right side
   3,870.64x = 13,112,108.49
5. Step 5: Solve for x
   x = 13,112,108.49/3,870.64
6. Step 6: Final answer
   x = 3,387.58