Finding the Fourth Proportional to 2,653.12, 3,977.04 and 920.56

Step by Step Solution

1. Step 1: Write the proportion equation
   2,653.12 : 3,977.04 = 920.56 : x
2. Step 2: Convert to fraction form
   2,653.12/3,977.04 = 920.56/x
3. Step 3: Cross multiply
   2,653.12x = 3,977.04 × 920.56
4. Step 4: Simplify right side
   2,653.12x = 3,661,103.94
5. Step 5: Solve for x
   x = 3,661,103.94/2,653.12
6. Step 6: Final answer
   x = 1,379.92