Finding the Fourth Proportional to 78,506.63, 117,798.90 and 31,120.72

Step by Step Solution

1. Step 1: Write the proportion equation
   78,506.63 : 117,798.90 = 31,120.72 : x
2. Step 2: Convert to fraction form
   78,506.63/117,798.90 = 31,120.72/x
3. Step 3: Cross multiply
   78,506.63x = 117,798.90 × 31,120.72
4. Step 4: Simplify right side
   78,506.63x = 3,665,986,172.01
5. Step 5: Solve for x
   x = 3,665,986,172.01/78,506.63
6. Step 6: Final answer
   x = 46,696.52