Finding the Fourth Proportional to 100.72, 139.06 and 82.34

Step by Step Solution

1. Step 1: Write the proportion equation
   100.72 : 139.06 = 82.34 : x
2. Step 2: Convert to fraction form
   100.72/139.06 = 82.34/x
3. Step 3: Cross multiply
   100.72x = 139.06 × 82.34
4. Step 4: Simplify right side
   100.72x = 11,450.20
5. Step 5: Solve for x
   x = 11,450.20/100.72
6. Step 6: Final answer
   x = 113.68