Finding the Fourth Proportional to 92,780, 139,055.84 and 42,790.72

Step by Step Solution

1. Step 1: Write the proportion equation
   92,780 : 139,055.84 = 42,790.72 : x
2. Step 2: Convert to fraction form
   92,780/139,055.84 = 42,790.72/x
3. Step 3: Cross multiply
   92,780x = 139,055.84 × 42,790.72
4. Step 4: Simplify right side
   92,780x = 5,950,299,513.80
5. Step 5: Solve for x
   x = 5,950,299,513.80/92,780
6. Step 6: Final answer
   x = 64,133.43