Finding the Fourth Proportional to 120,630.72, 166,476.96 and 78,225.60

Step by Step Solution

1. Step 1: Write the proportion equation
   120,630.72 : 166,476.96 = 78,225.60 : x
2. Step 2: Convert to fraction form
   120,630.72/166,476.96 = 78,225.60/x
3. Step 3: Cross multiply
   120,630.72x = 166,476.96 × 78,225.60
4. Step 4: Simplify right side
   120,630.72x = 13,022,760,082.18
5. Step 5: Solve for x
   x = 13,022,760,082.18/120,630.72
6. Step 6: Final answer
   x = 107,955.59