Finding the Fourth Proportional to 78,801.70, 108,747.18 and 42,991.60

Step by Step Solution

1. Step 1: Write the proportion equation
   78,801.70 : 108,747.18 = 42,991.60 : x
2. Step 2: Convert to fraction form
   78,801.70/108,747.18 = 42,991.60/x
3. Step 3: Cross multiply
   78,801.70x = 108,747.18 × 42,991.60
4. Step 4: Simplify right side
   78,801.70x = 4,675,215,263.69
5. Step 5: Solve for x
   x = 4,675,215,263.69/78,801.70
6. Step 6: Final answer
   x = 59,328.86