Finding the Fourth Proportional to 90,399.64, 135,422.94 and 42,947.20

Step by Step Solution

1. Step 1: Write the proportion equation
   90,399.64 : 135,422.94 = 42,947.20 : x
2. Step 2: Convert to fraction form
   90,399.64/135,422.94 = 42,947.20/x
3. Step 3: Cross multiply
   90,399.64x = 135,422.94 × 42,947.20
4. Step 4: Simplify right side
   90,399.64x = 5,816,036,088.77
5. Step 5: Solve for x
   x = 5,816,036,088.77/90,399.64
6. Step 6: Final answer
   x = 64,336.94