Finding the Fourth Proportional to 78,991.30, 109,010.09 and 47,178.55

Step by Step Solution

1. Step 1: Write the proportion equation
   78,991.30 : 109,010.09 = 47,178.55 : x
2. Step 2: Convert to fraction form
   78,991.30/109,010.09 = 47,178.55/x
3. Step 3: Cross multiply
   78,991.30x = 109,010.09 × 47,178.55
4. Step 4: Simplify right side
   78,991.30x = 5,142,937,981.57
5. Step 5: Solve for x
   x = 5,142,937,981.57/78,991.30
6. Step 6: Final answer
   x = 65,107.65