Finding the Fourth Proportional to 78,720.79, 108,632.53 and 42,911.50

Step by Step Solution

1. Step 1: Write the proportion equation
   78,720.79 : 108,632.53 = 42,911.50 : x
2. Step 2: Convert to fraction form
   78,720.79/108,632.53 = 42,911.50/x
3. Step 3: Cross multiply
   78,720.79x = 108,632.53 × 42,911.50
4. Step 4: Simplify right side
   78,720.79x = 4,661,584,811.10
5. Step 5: Solve for x
   x = 4,661,584,811.10/78,720.79
6. Step 6: Final answer
   x = 59,216.69