Finding the Fourth Proportional to 106.78, 147.24 and 86.00

Step by Step Solution

1. Step 1: Write the proportion equation
   106.78 : 147.24 = 86.00 : x
2. Step 2: Convert to fraction form
   106.78/147.24 = 86.00/x
3. Step 3: Cross multiply
   106.78x = 147.24 × 86.00
4. Step 4: Simplify right side
   106.78x = 12,661.90
5. Step 5: Solve for x
   x = 12,661.90/106.78
6. Step 6: Final answer
   x = 118.58