Finding the Fourth Proportional to 106.29, 146.58 and 78.72

Step by Step Solution

1. Step 1: Write the proportion equation
   106.29 : 146.58 = 78.72 : x
2. Step 2: Convert to fraction form
   106.29/146.58 = 78.72/x
3. Step 3: Cross multiply
   106.29x = 146.58 × 78.72
4. Step 4: Simplify right side
   106.29x = 11,538.78
5. Step 5: Solve for x
   x = 11,538.78/106.29
6. Step 6: Final answer
   x = 108.56