Finding the Fourth Proportional to 77,891.70, 107,490.63 and 42,081.78

Step by Step Solution

1. Step 1: Write the proportion equation
   77,891.70 : 107,490.63 = 42,081.78 : x
2. Step 2: Convert to fraction form
   77,891.70/107,490.63 = 42,081.78/x
3. Step 3: Cross multiply
   77,891.70x = 107,490.63 × 42,081.78
4. Step 4: Simplify right side
   77,891.70x = 4,523,397,043.72
5. Step 5: Solve for x
   x = 4,523,397,043.72/77,891.70
6. Step 6: Final answer
   x = 58,072.90