Finding the Fourth Proportional to 12,288.56, 18,436.91 and 4,891.05

Step by Step Solution

1. Step 1: Write the proportion equation
   12,288.56 : 18,436.91 = 4,891.05 : x
2. Step 2: Convert to fraction form
   12,288.56/18,436.91 = 4,891.05/x
3. Step 3: Cross multiply
   12,288.56x = 18,436.91 × 4,891.05
4. Step 4: Simplify right side
   12,288.56x = 90,175,824.20
5. Step 5: Solve for x
   x = 90,175,824.20/12,288.56
6. Step 6: Final answer
   x = 7,338.20