Finding the Fourth Proportional to 111,336.50, 166,586.25 and 78,121.37

Step by Step Solution

1. Step 1: Write the proportion equation
   111,336.50 : 166,586.25 = 78,121.37 : x
2. Step 2: Convert to fraction form
   111,336.50/166,586.25 = 78,121.37/x
3. Step 3: Cross multiply
   111,336.50x = 166,586.25 × 78,121.37
4. Step 4: Simplify right side
   111,336.50x = 13,013,946,073.16
5. Step 5: Solve for x
   x = 13,013,946,073.16/111,336.50
6. Step 6: Final answer
   x = 116,888.41