Finding the Fourth Proportional to 42,755.94, 64,147.86 and 20,571.12

Step by Step Solution

1. Step 1: Write the proportion equation
   42,755.94 : 64,147.86 = 20,571.12 : x
2. Step 2: Convert to fraction form
   42,755.94/64,147.86 = 20,571.12/x
3. Step 3: Cross multiply
   42,755.94x = 64,147.86 × 20,571.12
4. Step 4: Simplify right side
   42,755.94x = 1,319,593,325.80
5. Step 5: Solve for x
   x = 1,319,593,325.80/42,755.94
6. Step 6: Final answer
   x = 30,863.39